US90 points/condenser upgrade to 110 CDI - anyone try it?

[350x'inNY]

Have a old school Joker frame and a US90 chromed carrier/sprocket/brake assembly laying around here for years. Decided I will finally put it together. I have another US90 motor that 'lost spark'.... is there any way to upgrade the ignition to a later model 110 with the CDI???

Thanks
Bruce

[trizilla]

the 90's used an inner rotor and the cdi 110's used an outer. your problem is gonna be at the crankshaft trying to get the late model stuff to fit. i think a fella on this board did this conversion but it sounded like alot of work.

[tblumer]

A guy over on the CT90 yahoo group converted a points motor on his CT90 to cdi using ATC110 parts. I think it's doable but won't be just a parts swap.

[tblumer]

I uploaded a pdf of Scott Kirns' cdi conversion

https://www.box.com/s/sda2d235kxsa4xnpm6q5

[350x'inNY]

I uploaded a pdf of Scott Kirns' cdi conversion

https://www.box.com/s/sda2d235kxsa4xnpm6q5

Thanks man... a lot to digest there, but looks like a lot of it will switch over. Thank again...

[shortline10]

I have this atc90/110 points eliminator setup , kinda neat piece of old school history . Came in a parts lot that I picked up and I haven't tried it yet .

[350x'inNY]

I have this atc90/110 points eliminator setup , kinda neat piece of old school history . Came in a parts lot that I picked up and I haven't tried it yet .

That is pretty neat!

PS - Joker frame on ebay. Search Honda Joker Frame

[shortline10]

Yeah I seen that frame for sale . I have a pile of aftermarket frames as well ... you need one LOL ?????



That is pretty neat!

PS - Joker frame on ebay. Search Honda Joker Frame

[tblumer]

Same guy has a Nicholson up too, think he had a Pauter for sale a while back.

[350x'inNY]

Since I got a couple of you Joker frame guys on the line.... will any US90 - ATC90 - ATC110/125 set of forks mount to the steering stem? I am hoping to use a US90 set of forks and such, as the rear carrier/axle that was with the frame was a US90 setup.

Bruce

[tblumer]

They should, i just popped a set of all balls taper bearings and 90 forks on mine. With some slight trimming on the forks you can pop on 185/200s forks too.

[trike savior]

all the 90/110/125 frames have same neck so any frame will accept any triple tree. I have 200 s springer forks on my 125m's .you have to cut off the steering stop on the frame but they go right on.

I was going to do same thing with switching a 90 motor to cdi stuff but the crankshafts are different where the flywheel mounts. and as someone said one used inner rotor and other outer rotor so the case is different as well. and you have to switch those parts because points bikes are 6 volt and cdi is 12 volt. buy a cdi motor.

[tblumer]

I was going to do same thing with switching a 90 motor to cdi stuff but the crankshafts are different where the flywheel mounts. and as someone said one used inner rotor and other outer rotor so the case is different as well. and you have to switch those parts because points bikes are 6 volt and cdi is 12 volt. buy a cdi motor.

I assume you didn't look at the pdf I posted. Alternator appears same as atc90.

[350x'inNY]

I ended up buying a 110 CDI motor with complete wiring harness and new carb on CL last night. I guess it's going to be a US90-110 mutt with each generation of 90/110s being represented.

[trike savior]

the way I was talking about was using all the parts from a cdi motor on a points motor but for all the work it takes it is not worth it. my info comes from personally having these two motors side by side on the bench. the points bike and cdi bike have big differences. not in the parts on the cam but the parts on the crank. and I know one is 6 and one 12 because they use different volt light bulbs. but that is just the lighting side of the generator. the ignition side of the generator is different and cdi uses a lot more voltage than points. that is why the pdf explains that he had to rewire the generator. it looks like he used the original generator parts but rewound it with the proper wire to get the voltage needed to run cdi. pdf says 25 volts which sounds about right.

if you have the expertise to rewind the generator coils like in the pdf then do it but doing that is something that is easy to get things wrong and have it not work. if you can do that you will have power to run cdi and still use 6 volt lighting system

[trike savior]

sounds like you made the right and easy choice. the cdi 110's have a bit more power so it should work out nice. good luck

[350x'inNY]

About the front ends.... I was given a 250SX front end... would that go on similar to a 185/200? If too tall I could slide the forks down if the triples would mount.

[trike savior]

no it will not fit. 250 sx has larger mounting tube and therefore larger bearing races that wont fit the 90/110/125. ive never tried it but I know for sure the size difference is quite a bit.

[350x'inNY]

Yep... I see that now... they use the 1/4" ball bearings like the 250R 200X and 350X. Darn.

[TRIPOD guy]

Just picked up a 73 us90 110 top end and cdi no pull start and sub trans parts missing don't know if it sparks yet look like stock parts will this work or am I wasting time

[shortline10]

Lots of differences and the short answer in no , even though the motors look the same Topend parts don’t interchange without lots of mods . Bores , strokes all different , electrical if CDI definitely different ,