Post by olyman on Jan 22, 2020 23:26:52 GMT
Blizzard GR
I am doing a rebuild of 1970 340 single Blizzard for friend. His original CD ignition is gone and instead of points he would like me to check into doing a modern CD conversion. I see the mid 1980's Citation LS is CD, has anyone tried that or???
Thanks!
John
Nico
Hi John,
I've been thinking about this! There's 2 problems. First is easy, the CDI stator plate won't bolt onto the crankcase but drilling some new holes will fix that. The diameter should be the same. It may even be possible to bolt the CDI parts onto a points plate.
Next problem is the flywheel won't fit on the crank either. What I'm thinking is take the center from a points flywheel that will fit on the crank, and the magnets off a CDI flywheel, and hope you can bolt them together. Then figure out a way to get both of them in the correct position and it might just work
Blizzard GR
Hi Nico,
Good to hear from you! I know the guys in vintage racing that have done ND conversions to their twin and triple Rotax engines have the case milled to accept the ND stator and then they have the hub cut out of the Bosch flywheel and pressed into the ND flywheel so it will go on the crank. I would assume this could be done here also?
Nico
That's pretty much what I was thinking, yes.
I'm not sure if it needs to be all that complicated though, the flywheel is attached to the hub just with a couple of bolts and it may be possible to just move it to another hub. It kind of depends what kind of ignition you want to use, I guess.
Once you have a flywheel that will fit on the crank, the stator plate should be easy I know that for the 277 CDI you are thinking of, the stator plate has the same diameter as the Bosch points plates, but they don't use the same bolt holes in the housing. If you can fix that by drilling a new hole or 2 in the plate, it should bolt right on without having to do any machine work on the case.
j3greg
Bosch and ND flywheels are both 4 magnet - should be no issues using
Problem is relation of keyway to magnets to TDC - need to re-key flywheel (use 1 existing mtg hole and drill 1 ) or properly position Stator using two new holes
hermit
lowtek may be the guy to talk to. I think he may have dabbled with the twins and might know about the singles. The blizzard bases have been machined differently than tnt and oly so may accept the cdi stator more readily seeing they had a form of cdi to start with if his base was original Blizz. I know my 246 looks very different than a tnt style. I may snap a pic later.
Blizzard GR
I have a couple of leads on a Citation CD system and if they come through I will take some photos and document it on here. If the stator is the same size as the old points unit, that would take the milling out of the equation which would be great.
j3greg, thanks for your input also. Just so I understand, are you saying that the Bosch flywheel can be used with the ND stator (but re-key it), or did I understand that wrong?
Neat stuff! John
hermit
Cool. There are some great resources here and guys have done some neat retrofittings. I would imagine the single has to be amongst the easiest to make work.
Blizzard GR
This site is soooo awesome. I can't thank Monty, you Tim, and the others enough for your hard work and help. First class all the way
John
decoy706
John
Please remember to save the project for the rest of us as I don't want to use my NOS CDI for the Blizzard singles unless I have to. Been saving it for a long time
Blizzard GR
Will do, Decoy!
The owner is working on finding a Citation CD system and I will post some pics once he gets one over to me and then I will start the process on here (unless someone else wants to start it on here, which would be great also).
Thanks!
John
j3greg
OK - Had been holding on to this thinking it might be a business opportunity - but what the hey who says I’m a good business guy ….. And in full disclosure mode - I have not done this on a 335 yet but have done it on a 277 and everything looks to measure up correctly on a 335/340 and most likely all singles using a Bosch point system
The Ultralight community has been converting 277 Bosch point systems to ND CDI for years
There is a company in Arizona - Airscrew performance Sells the complete conversion kit $275 (last year) Its a proven system and if fly guys run it should be ok on track or trail. I feel worth the money
however if you would rather gather parts yourself keep reading
The 277 point flywheel magnet ring is the same diameter as the 335/340 and other singles It may actually be the same - but I have haven't dug into part numbers
The 277 point flywheel uses 4 magnets same as 335/340 point and 277 ND CDI flywheel
What you need - but what's in the kit may not be what I reference from aftermarket snow suppliers
Item rotax # aftermarket
1) CDI box Rotax 420-866-595 Kimpex 01-299
2) stator gen coil 420-866-635 Marshall 11-1347
3) external ign coil 420-866-660 Mfg supply 01-113
4) roll pin NA 5/32 pin
Or get yourself a few used parts. The stator coil and the CDI box are the same that were used on most trail sleds between mid 80's and early 90s The key to identifying a ND stator - is the horseshoe shaped lighting coil. When you look up these parts you will see how one size fits all they are
The first part is pretty easy - the CDI trigger coil assembly is the same size and shape as the ignition coil on a point Stator
Take your coil off the point stator (internal ignition or charging coil if external ign). Bolt in the CDI coil Your lighting coil stays
On the outside find a place to bolt the coil and box
Run the wires between the three pieces ( if you are using new parts you will need to hard wire the stator coil to the box it does not come with the plug )
Part two not really hard but kinda a PIA
Put the flywheel on - loose nut no key find a convenient place to put a mark on the case - rotate the flywheel to top dead center - mark the flywheel opposite the mark on the case .
Now here comes the tedious part . Spin the engine by hand - like you were starting it - with a timing light see where it is firing in relation to the TDC marks Move the flywheel to get it closer try again
Ultimately what you are trying to do is get the engine firing at TDC “AT CRANKING SPEED”. The beauty is - the CDI box will advance it automatically from there when the engine is actually running.
Step Three - The hard part - Once you know where the flywheel needs to be - you need to lock it down. One way is to re-cut the keyway in the flywheel in the correct spot
The other way is what the Arizona kit does - using a drill bit - drill straight into the crankshaft where the current flywheel keyway is - insert a roll-pin in place of the true key. Put the nut back on and away you go.
That’s it your done - Royalty payments can be sent to me
The Stators
The "Kit from Arizona"
hermit
Very cool. I've read several articles those ultralight guys have written and truthfully discredited much due to the 277 thing and having "old school" engines and a very good portion is like reading Greek to me with limited knowledge of what they're talking about. Also the Kimpex cdi's always scared me. But obviously you've done your research and that's apparent. There is still no reason why you couldn't assemble the same essential parts and sell your own version of these to people interested. Many guys(myself included) really don't want to have to think about what items to get parts etc so is easier to just go to a guy and lay out the money for what he has. I've done it many times with the Tillotson parts and some Bosch parts, but remembering which cdi box and coils part numbers for this project would be more than I want to remember. It is a great thing that you've shared and really will apply to a small percentage who are after more than the standard points and condenser have to offer. Almost seems enticing for my 246 engine but am not racing nor even looking for any addl power so the points conversion will suffice. Thank you for sharing.
j3greg
Hey Hermit- Really not worried about the business side of this- cuz any profits would just be plowed back into some thing old and yellow anyway
Real concern for not posting sooner was I haven't actually done it on my TNT yet . I have all the parts - did all the homework - am 99.99% sure - but you never know till you fire it up
Rotax never offically sold any aircraft engines with CDI untill they brought out the redudant systems. Lots of guys converted to snowmobile systems on their own.
I never flew behind one for the reason you mentioned- snow guys complainig about Kimpex electrics. Points served me well. On the other hand never had anybody in our club lose a 277 CDI ignition mid-flight either.
But when we started running citations was not at all impressed with the fact there is no advance mechanism. Lots of compression, full advance when pulling the rope - doesn't sit well with flimsy plastic recoil parts And they just seem to start and idle better
Can't say they are any faster ...
hermit
I have the original Bosch cdi for my 246 and it did spark when I got the engine. I will have the external box mounted with the appearance it's functional but have a new points stator from a twin I will be using for fire. One issue with these machines is the crank taper is different from the singles and twins. The Blizzard singles actually hav ethe same taper as the twins, but not the same as singles? so you have to run the twin flywheel when converting over to points IF you have the orig Blizzard crank. Lucky for me I do. I've thought maybe I'd try the orig cdi but I don't want to be messing with it. I'd rather sacrifice the little possible rpm loss with points in favor of reliability. MAny guys have confusion and feel points aren't as reliable as cdi so they want to change them. My understanding is the points aren't as capable of achieving the high rpm without floating and ignition curves are not as controlled as with electronics. Anyhow I'll be curious how it all works out.
j3greg
Hermit -
the amazig thing about converting ths way is that it APPEARS almost any Bosch points stator can be converted in this manner it makes no difference twin or single
the only change to the point stator is changing the ignition coil
the only change to any flywheel is the new keyway
I know it works on a 277 or 377
the twins use a different external coil because it has two plug wires - but the CDI unit and stator coil is the same
If you find the used parts from any 82-89 sled you have all the parts. Even the twin coil can be used on a single - just use one plug wire
Again there really is no huge improvement in using this system over a PROPERLY working point system
point float is an exageration - old v-8 cars povide 16,000 sparks a minute - sleds are doing 8000
It does provide a much stronger- hgher voltage spark so you can run richer (cooler) and not run foul plugs
this vintage CDI does not help perfomance much because the timing curve is really no different than a point system Fully advanced at a certain RPM usually 6000
Modern systems actually RETARD the timing giving as much as 25-30 advance at low rpm and then backing off to around 10 degrees at 8500 rpm
Let us know what you do with the 246
lowtekrednek
the nippondenso ignition system bolts on and works for most of the free air twins, with the exception of the 72 400 tnt fa, and the 77-78 tnt free air.
I honestly do not know if it works on the RV free air engines.
the difference is in the crank stub diameter, the ones that are not a direct fit have a smaller stub on the ignition side.
one possible way around this would be to find the early nippon ignition out of a 9500 blizzard, as they have a smaller flywheel hole, I am still researching that.
the above may work for the singles too...
j3greg, after talking to you at st germain, I went home and tried the nip flywheel on a 292 crank, and the hole in the flywheel is larger than the stub on the crank.
there are two things that need to be done when converting the points to CD on the twin (I know, wrong section)
you will need to make the hole in the crankcase larger to fit the CD plug thru, and you need to make new timing marks.
lowtekrednek
ok.... heres the deal,
the single cyl crank is smaller than the early type 454 nippondenso flywheel hole.
Some machining will be necessary
Vintage Elan Guy
I made the topic a sticky so it won't get lost or deleted, hopefully.
Always best to save it on your computer if you want to preserve the info for yourself.
Rob Noakes
Bones
I know about nothing about Ski-Doo/Rotax CD systems after 1980 ( that dates me )
What triggers the spark on the (say ) Nipp ignition from the 377
If the 277/377 hub fits the early TnT F/As then it ain`t gonna fit on any other `70s Rotax, other than maybe the early F/A blizzards, I doo not know about them. The `73/75 F/As have the biggest crank stub of all the `70s engines. The 340 RV is a fairly tiny stub.
On the `70s engines there is a few different crank stub sizes, several different locations for key way in relation to piston(s) TDC & 2 different key sizes.
If the 277/377 ignition triggers from the magnet ring then you might ? be able to mount the 277 mag ring onto the hub from the engine you are converting to
If it triggers from the hub, well then the ring swab ain`t gonna work.
Bones
lowtekrednek
on the twins (73-75 free air) the key is at the 12 o clock position when the mag side piston is at tdc, on the mid 80s doos the key is at about 3 o clock (most are, some are 9 o clock), BUT the stator is also twisted to make up for the difference.
thanks, Bones for the clarification on the RV stuff, and the blizzard stuff.
my 645 has a really small shaft in the mag side, so, i have a hunch that the twins might be the same...
oh yeah, the trigger on the nipp is that there is a magnet in the flywheel that is opposite pole as the other three
j3greg
oh yeah, the trigger on the nipp is that there is a magnet in the flywheel that is opposite pole as the other three
That's right LowTek - it is the changing polarity that triggers the ND system.
However - the 277 has TWO alternate sets two magnets one way two magnets the other. That is why the same magnet ring works on both the 277 and 377 the spark happens at both TDC and BDC on both cylinders. (even the 277 get two sparks)
So far every other single cylinder flywheel I have - 292/300/335/340 has the same arrangement 4 magnets and 2 sets of polarity (I check with a small maget - either attracks or repels)
Sorta Makes Sense - that arrangement creates AC power - that's why Electric Start Models need rectifier to charge battery
When we talked at St Germain - I wasn't sure about that
. Now it would seem the hub is of no concern. Use whatever fits your particular engine
Use the standard flywheel and just re-key to proper spot (same for twins)
Key thing to be sure of - 4 magnets - opposite polarity sets - and the same diameter magnet ring.
Blizzard GR
j3greg, (and others also!), I want to send out a big THANK YOU for keeping this post going and sharing your knowledge. My friend has exhausted all contacts looking for Citation CD units over the past week and I thought we were done - so now after reading these posts, this breathes new life into this. I have been gone for work and just got back and was excited to read all this. Wow you guys are amazing with this information!
lowtekrednek
still trying to research the one lunger conversion, my magnet testing has been inconclusive, might have to just try it.
j3greg
Lowtek - I use one of those little screwdrivers with the magnet in the end - let it swing in your fingers
trick is to do it in the middle of the magnet - not the ends
my camera doesn't do good close ups but here is how I do it
Attract
Repel
lowtekrednek
i will re-try it
Then have to figure out where to locate the exciter coil
Blizzard GR
Hi guys,
I have been playing around with a unit also, etc and I will have an update and questions soon
Thanks!
John
Blizzard GR
OK guys, here is another option I have been looking at for the last 2 months. It has been so busy, that I haven’t updated here lately.
Anyway, a friend had a 1975 Can-am 250 bike that was blown and he let me look at it for I had an idea that came to me about the CD on those bikes. I used to race a Can-am MX1 in motocross that I bought new in 1974, so I was familiar with those ignitions.
My friend let me I pull the flywheel off his and the stator and I was impressed in that I think it would work if I used an alum plate behind it (ala 1976 RV super mod kit) to put the stator in and then bolt it into the case. I started doing more research on these Can-am ignitions and it looks like in 1977 they went to a 6 pole unit and used the same CD box as the 1977 CC RV and the 440 oval Blizzards. My friend said this summer he would let me play with the ignition on a single Blizzard. There seems to be a good supply of Can-am ignitions at bike salvage yards. I love the look of the little silver CD box on the 1974-76 Can-am's.
I don’t know if the hub in the flywheel is the same as the single Blizzard, but seeing the hub is riveted, I think I could swap out the hub.
What do you guys think? Anyone been down this road?
hermit
The guy at Label X Motorsports just advertised they have a Nipp CDI for TNt singles so it has to work with the Blizz if they made the taper the same as a twin which is what the single blizzards have. Just a thought. Someone could call LabelX.
j3greg
The guy at Label X Motorsports just advertised they have a Nipp CDI for TNt singles so it has to work with the Blizz if they made the taper the same as a twin which is what the single blizzards have. Just a thought. Someone could call LabelX.
Where did they Advertise?
decoy706
Here's his add it's posted here
new 340 crankshafts
We are having a run of 340 single cyl cranks built for racing engines, much like our 292 Yami cranks that are a must in the open classes. The changes to the stock design are (off the shelf) dual bearing PTO end, larger journals both MAG and PTO for more strength, an off the shelf late model Ski Doo connecting rod, a revised PTO seal plate, and the common 30mm taper on the PTO end for use with a Cat or Polaris primary for the ultimate performance in the open classes.
These will be available beginning of July. Please call us to reserve one. We will offer a package deal this summer for someone interested in sending their cases to us and let us professionally assemble the bottom end with new seals and complete gasket set. Optional Nip CDI ignitions upon request.
Call Label X Motorsports at (207) 933-3120
70Oly399
I just picked up three citation LS from 86-87 with the 253 single. I haven't really looked yet but it seems like I can make 2 good riders and the third is a parts sled. Engine #3 is seized up so I may try my hand at using its ignition on a 340 single. This thread has given me some idea where to start my research. Keep the info coming.
Erich
lowtekrednek
I have a new idea......
gonna do some cutting and drilling today
lowtekrednek
some machining.......
lowtekrednek
the parts are at a friends place getting machined,
yes, I am a machinist by trade, but would rather fabricate than machine, so I trade skills with my friend.
we will have results soon
SurgeSurge
Sweet I cant wait to be part of this!!!!
swamprat
I'm a new be on this site,but i'm glad i'm here this is some great info,can i steal the info for non yellow use,and yellow also of course ,thanks!!
Poidy
that the same as this which was mentioned on FB elan site? www.facebook.com/RMStator/?hc_ref=ARRd5igm8RA0tW1XiHkbsJ43Wb8d9BwvlmA2IvsVo9Atet0exs5pNCMjr5RXARQbz8E&fref=gs&dti=165106703511686&hc_location=group
RMStator?
I am doing a rebuild of 1970 340 single Blizzard for friend. His original CD ignition is gone and instead of points he would like me to check into doing a modern CD conversion. I see the mid 1980's Citation LS is CD, has anyone tried that or???
Thanks!
John
Nico
Hi John,
I've been thinking about this! There's 2 problems. First is easy, the CDI stator plate won't bolt onto the crankcase but drilling some new holes will fix that. The diameter should be the same. It may even be possible to bolt the CDI parts onto a points plate.
Next problem is the flywheel won't fit on the crank either. What I'm thinking is take the center from a points flywheel that will fit on the crank, and the magnets off a CDI flywheel, and hope you can bolt them together. Then figure out a way to get both of them in the correct position and it might just work
Blizzard GR
Hi Nico,
Good to hear from you! I know the guys in vintage racing that have done ND conversions to their twin and triple Rotax engines have the case milled to accept the ND stator and then they have the hub cut out of the Bosch flywheel and pressed into the ND flywheel so it will go on the crank. I would assume this could be done here also?
Nico
That's pretty much what I was thinking, yes.
I'm not sure if it needs to be all that complicated though, the flywheel is attached to the hub just with a couple of bolts and it may be possible to just move it to another hub. It kind of depends what kind of ignition you want to use, I guess.
Once you have a flywheel that will fit on the crank, the stator plate should be easy I know that for the 277 CDI you are thinking of, the stator plate has the same diameter as the Bosch points plates, but they don't use the same bolt holes in the housing. If you can fix that by drilling a new hole or 2 in the plate, it should bolt right on without having to do any machine work on the case.
j3greg
Bosch and ND flywheels are both 4 magnet - should be no issues using
Problem is relation of keyway to magnets to TDC - need to re-key flywheel (use 1 existing mtg hole and drill 1 ) or properly position Stator using two new holes
hermit
lowtek may be the guy to talk to. I think he may have dabbled with the twins and might know about the singles. The blizzard bases have been machined differently than tnt and oly so may accept the cdi stator more readily seeing they had a form of cdi to start with if his base was original Blizz. I know my 246 looks very different than a tnt style. I may snap a pic later.
Blizzard GR
I have a couple of leads on a Citation CD system and if they come through I will take some photos and document it on here. If the stator is the same size as the old points unit, that would take the milling out of the equation which would be great.
j3greg, thanks for your input also. Just so I understand, are you saying that the Bosch flywheel can be used with the ND stator (but re-key it), or did I understand that wrong?
Neat stuff! John
hermit
Cool. There are some great resources here and guys have done some neat retrofittings. I would imagine the single has to be amongst the easiest to make work.
Blizzard GR
This site is soooo awesome. I can't thank Monty, you Tim, and the others enough for your hard work and help. First class all the way
John
decoy706
John
Please remember to save the project for the rest of us as I don't want to use my NOS CDI for the Blizzard singles unless I have to. Been saving it for a long time
Blizzard GR
Will do, Decoy!
The owner is working on finding a Citation CD system and I will post some pics once he gets one over to me and then I will start the process on here (unless someone else wants to start it on here, which would be great also).
Thanks!
John
j3greg
OK - Had been holding on to this thinking it might be a business opportunity - but what the hey who says I’m a good business guy ….. And in full disclosure mode - I have not done this on a 335 yet but have done it on a 277 and everything looks to measure up correctly on a 335/340 and most likely all singles using a Bosch point system
The Ultralight community has been converting 277 Bosch point systems to ND CDI for years
There is a company in Arizona - Airscrew performance Sells the complete conversion kit $275 (last year) Its a proven system and if fly guys run it should be ok on track or trail. I feel worth the money
however if you would rather gather parts yourself keep reading
The 277 point flywheel magnet ring is the same diameter as the 335/340 and other singles It may actually be the same - but I have haven't dug into part numbers
The 277 point flywheel uses 4 magnets same as 335/340 point and 277 ND CDI flywheel
What you need - but what's in the kit may not be what I reference from aftermarket snow suppliers
Item rotax # aftermarket
1) CDI box Rotax 420-866-595 Kimpex 01-299
2) stator gen coil 420-866-635 Marshall 11-1347
3) external ign coil 420-866-660 Mfg supply 01-113
4) roll pin NA 5/32 pin
Or get yourself a few used parts. The stator coil and the CDI box are the same that were used on most trail sleds between mid 80's and early 90s The key to identifying a ND stator - is the horseshoe shaped lighting coil. When you look up these parts you will see how one size fits all they are
The first part is pretty easy - the CDI trigger coil assembly is the same size and shape as the ignition coil on a point Stator
Take your coil off the point stator (internal ignition or charging coil if external ign). Bolt in the CDI coil Your lighting coil stays
On the outside find a place to bolt the coil and box
Run the wires between the three pieces ( if you are using new parts you will need to hard wire the stator coil to the box it does not come with the plug )
Part two not really hard but kinda a PIA
Put the flywheel on - loose nut no key find a convenient place to put a mark on the case - rotate the flywheel to top dead center - mark the flywheel opposite the mark on the case .
Now here comes the tedious part . Spin the engine by hand - like you were starting it - with a timing light see where it is firing in relation to the TDC marks Move the flywheel to get it closer try again
Ultimately what you are trying to do is get the engine firing at TDC “AT CRANKING SPEED”. The beauty is - the CDI box will advance it automatically from there when the engine is actually running.
Step Three - The hard part - Once you know where the flywheel needs to be - you need to lock it down. One way is to re-cut the keyway in the flywheel in the correct spot
The other way is what the Arizona kit does - using a drill bit - drill straight into the crankshaft where the current flywheel keyway is - insert a roll-pin in place of the true key. Put the nut back on and away you go.
That’s it your done - Royalty payments can be sent to me
The Stators
The "Kit from Arizona"
hermit
Very cool. I've read several articles those ultralight guys have written and truthfully discredited much due to the 277 thing and having "old school" engines and a very good portion is like reading Greek to me with limited knowledge of what they're talking about. Also the Kimpex cdi's always scared me. But obviously you've done your research and that's apparent. There is still no reason why you couldn't assemble the same essential parts and sell your own version of these to people interested. Many guys(myself included) really don't want to have to think about what items to get parts etc so is easier to just go to a guy and lay out the money for what he has. I've done it many times with the Tillotson parts and some Bosch parts, but remembering which cdi box and coils part numbers for this project would be more than I want to remember. It is a great thing that you've shared and really will apply to a small percentage who are after more than the standard points and condenser have to offer. Almost seems enticing for my 246 engine but am not racing nor even looking for any addl power so the points conversion will suffice. Thank you for sharing.
j3greg
Hey Hermit- Really not worried about the business side of this- cuz any profits would just be plowed back into some thing old and yellow anyway
Real concern for not posting sooner was I haven't actually done it on my TNT yet . I have all the parts - did all the homework - am 99.99% sure - but you never know till you fire it up
Rotax never offically sold any aircraft engines with CDI untill they brought out the redudant systems. Lots of guys converted to snowmobile systems on their own.
I never flew behind one for the reason you mentioned- snow guys complainig about Kimpex electrics. Points served me well. On the other hand never had anybody in our club lose a 277 CDI ignition mid-flight either.
But when we started running citations was not at all impressed with the fact there is no advance mechanism. Lots of compression, full advance when pulling the rope - doesn't sit well with flimsy plastic recoil parts And they just seem to start and idle better
Can't say they are any faster ...
hermit
I have the original Bosch cdi for my 246 and it did spark when I got the engine. I will have the external box mounted with the appearance it's functional but have a new points stator from a twin I will be using for fire. One issue with these machines is the crank taper is different from the singles and twins. The Blizzard singles actually hav ethe same taper as the twins, but not the same as singles? so you have to run the twin flywheel when converting over to points IF you have the orig Blizzard crank. Lucky for me I do. I've thought maybe I'd try the orig cdi but I don't want to be messing with it. I'd rather sacrifice the little possible rpm loss with points in favor of reliability. MAny guys have confusion and feel points aren't as reliable as cdi so they want to change them. My understanding is the points aren't as capable of achieving the high rpm without floating and ignition curves are not as controlled as with electronics. Anyhow I'll be curious how it all works out.
j3greg
Hermit -
the amazig thing about converting ths way is that it APPEARS almost any Bosch points stator can be converted in this manner it makes no difference twin or single
the only change to the point stator is changing the ignition coil
the only change to any flywheel is the new keyway
I know it works on a 277 or 377
the twins use a different external coil because it has two plug wires - but the CDI unit and stator coil is the same
If you find the used parts from any 82-89 sled you have all the parts. Even the twin coil can be used on a single - just use one plug wire
Again there really is no huge improvement in using this system over a PROPERLY working point system
point float is an exageration - old v-8 cars povide 16,000 sparks a minute - sleds are doing 8000
It does provide a much stronger- hgher voltage spark so you can run richer (cooler) and not run foul plugs
this vintage CDI does not help perfomance much because the timing curve is really no different than a point system Fully advanced at a certain RPM usually 6000
Modern systems actually RETARD the timing giving as much as 25-30 advance at low rpm and then backing off to around 10 degrees at 8500 rpm
Let us know what you do with the 246
lowtekrednek
the nippondenso ignition system bolts on and works for most of the free air twins, with the exception of the 72 400 tnt fa, and the 77-78 tnt free air.
I honestly do not know if it works on the RV free air engines.
the difference is in the crank stub diameter, the ones that are not a direct fit have a smaller stub on the ignition side.
one possible way around this would be to find the early nippon ignition out of a 9500 blizzard, as they have a smaller flywheel hole, I am still researching that.
the above may work for the singles too...
j3greg, after talking to you at st germain, I went home and tried the nip flywheel on a 292 crank, and the hole in the flywheel is larger than the stub on the crank.
there are two things that need to be done when converting the points to CD on the twin (I know, wrong section)
you will need to make the hole in the crankcase larger to fit the CD plug thru, and you need to make new timing marks.
lowtekrednek
ok.... heres the deal,
the single cyl crank is smaller than the early type 454 nippondenso flywheel hole.
Some machining will be necessary
Vintage Elan Guy
I made the topic a sticky so it won't get lost or deleted, hopefully.
Always best to save it on your computer if you want to preserve the info for yourself.
Rob Noakes
Bones
I know about nothing about Ski-Doo/Rotax CD systems after 1980 ( that dates me )
What triggers the spark on the (say ) Nipp ignition from the 377
If the 277/377 hub fits the early TnT F/As then it ain`t gonna fit on any other `70s Rotax, other than maybe the early F/A blizzards, I doo not know about them. The `73/75 F/As have the biggest crank stub of all the `70s engines. The 340 RV is a fairly tiny stub.
On the `70s engines there is a few different crank stub sizes, several different locations for key way in relation to piston(s) TDC & 2 different key sizes.
If the 277/377 ignition triggers from the magnet ring then you might ? be able to mount the 277 mag ring onto the hub from the engine you are converting to
If it triggers from the hub, well then the ring swab ain`t gonna work.
Bones
lowtekrednek
on the twins (73-75 free air) the key is at the 12 o clock position when the mag side piston is at tdc, on the mid 80s doos the key is at about 3 o clock (most are, some are 9 o clock), BUT the stator is also twisted to make up for the difference.
thanks, Bones for the clarification on the RV stuff, and the blizzard stuff.
my 645 has a really small shaft in the mag side, so, i have a hunch that the twins might be the same...
oh yeah, the trigger on the nipp is that there is a magnet in the flywheel that is opposite pole as the other three
j3greg
oh yeah, the trigger on the nipp is that there is a magnet in the flywheel that is opposite pole as the other three
That's right LowTek - it is the changing polarity that triggers the ND system.
However - the 277 has TWO alternate sets two magnets one way two magnets the other. That is why the same magnet ring works on both the 277 and 377 the spark happens at both TDC and BDC on both cylinders. (even the 277 get two sparks)
So far every other single cylinder flywheel I have - 292/300/335/340 has the same arrangement 4 magnets and 2 sets of polarity (I check with a small maget - either attracks or repels)
Sorta Makes Sense - that arrangement creates AC power - that's why Electric Start Models need rectifier to charge battery
When we talked at St Germain - I wasn't sure about that
. Now it would seem the hub is of no concern. Use whatever fits your particular engine
Use the standard flywheel and just re-key to proper spot (same for twins)
Key thing to be sure of - 4 magnets - opposite polarity sets - and the same diameter magnet ring.
Blizzard GR
j3greg, (and others also!), I want to send out a big THANK YOU for keeping this post going and sharing your knowledge. My friend has exhausted all contacts looking for Citation CD units over the past week and I thought we were done - so now after reading these posts, this breathes new life into this. I have been gone for work and just got back and was excited to read all this. Wow you guys are amazing with this information!
lowtekrednek
still trying to research the one lunger conversion, my magnet testing has been inconclusive, might have to just try it.
j3greg
Lowtek - I use one of those little screwdrivers with the magnet in the end - let it swing in your fingers
trick is to do it in the middle of the magnet - not the ends
my camera doesn't do good close ups but here is how I do it
Attract
Repel
lowtekrednek
i will re-try it
Then have to figure out where to locate the exciter coil
Blizzard GR
Hi guys,
I have been playing around with a unit also, etc and I will have an update and questions soon
Thanks!
John
Blizzard GR
OK guys, here is another option I have been looking at for the last 2 months. It has been so busy, that I haven’t updated here lately.
Anyway, a friend had a 1975 Can-am 250 bike that was blown and he let me look at it for I had an idea that came to me about the CD on those bikes. I used to race a Can-am MX1 in motocross that I bought new in 1974, so I was familiar with those ignitions.
My friend let me I pull the flywheel off his and the stator and I was impressed in that I think it would work if I used an alum plate behind it (ala 1976 RV super mod kit) to put the stator in and then bolt it into the case. I started doing more research on these Can-am ignitions and it looks like in 1977 they went to a 6 pole unit and used the same CD box as the 1977 CC RV and the 440 oval Blizzards. My friend said this summer he would let me play with the ignition on a single Blizzard. There seems to be a good supply of Can-am ignitions at bike salvage yards. I love the look of the little silver CD box on the 1974-76 Can-am's.
I don’t know if the hub in the flywheel is the same as the single Blizzard, but seeing the hub is riveted, I think I could swap out the hub.
What do you guys think? Anyone been down this road?
hermit
The guy at Label X Motorsports just advertised they have a Nipp CDI for TNt singles so it has to work with the Blizz if they made the taper the same as a twin which is what the single blizzards have. Just a thought. Someone could call LabelX.
j3greg
The guy at Label X Motorsports just advertised they have a Nipp CDI for TNt singles so it has to work with the Blizz if they made the taper the same as a twin which is what the single blizzards have. Just a thought. Someone could call LabelX.
Where did they Advertise?
decoy706
Here's his add it's posted here
new 340 crankshafts
We are having a run of 340 single cyl cranks built for racing engines, much like our 292 Yami cranks that are a must in the open classes. The changes to the stock design are (off the shelf) dual bearing PTO end, larger journals both MAG and PTO for more strength, an off the shelf late model Ski Doo connecting rod, a revised PTO seal plate, and the common 30mm taper on the PTO end for use with a Cat or Polaris primary for the ultimate performance in the open classes.
These will be available beginning of July. Please call us to reserve one. We will offer a package deal this summer for someone interested in sending their cases to us and let us professionally assemble the bottom end with new seals and complete gasket set. Optional Nip CDI ignitions upon request.
Call Label X Motorsports at (207) 933-3120
70Oly399
I just picked up three citation LS from 86-87 with the 253 single. I haven't really looked yet but it seems like I can make 2 good riders and the third is a parts sled. Engine #3 is seized up so I may try my hand at using its ignition on a 340 single. This thread has given me some idea where to start my research. Keep the info coming.
Erich
lowtekrednek
I have a new idea......
gonna do some cutting and drilling today
lowtekrednek
some machining.......
lowtekrednek
the parts are at a friends place getting machined,
yes, I am a machinist by trade, but would rather fabricate than machine, so I trade skills with my friend.
we will have results soon
SurgeSurge
Sweet I cant wait to be part of this!!!!
swamprat
I'm a new be on this site,but i'm glad i'm here this is some great info,can i steal the info for non yellow use,and yellow also of course ,thanks!!
Poidy
that the same as this which was mentioned on FB elan site? www.facebook.com/RMStator/?hc_ref=ARRd5igm8RA0tW1XiHkbsJ43Wb8d9BwvlmA2IvsVo9Atet0exs5pNCMjr5RXARQbz8E&fref=gs&dti=165106703511686&hc_location=group
RMStator?