1969 CT70 K0 Flywheel problem

I am putting together the engine on my 1969 Trail 70 and had to buy a new crankshaft as the old one had a crank bearing go out. After installing the crankshaft and getting to the point where I needed to put on the used flywheel and it wouldn't go on all of the way. Is there any trick to fit an old flywheel to a new crankshaft? Or is there a problem with the old flywheel being shrunken some way with all of the heating and cooling?

Any inquiries would be appreciated.
 

kirrbby

Well-Known Member
Post pictures if you can. Old parts and new parts, and everything else would be nice too. We like pictures for sure.
There are a few different cranks, you could have bought a 12 volt style crankshaft, which is WAY different. Or maybe you don't even have the original engine in the first place. We're kinda flying blind on this end. Pictures and maybe links to the parts that you bought, could save us all a lot of unnecessary typing and wasted back and forth.
 

Gary

Well-Known Member
Any way I thought new 3 speed cranks were not to be found- only the 4 speed ones were available.
 
just a heads up though. it might be a little bit on pictures as I have to get the flywheel off the new crank. I have a puller on the way though. Once i get the flywheel off i will post the pictures on this thread
 

OLD CT

Well-Known Member
Post a picture of the ad for the new crank, looking at the picture might help too. ''New'' Ebay cranks from Malaysia that say fits a ct70, will not..
I was looking for a good 3 speed crank a couple years ago and knew they were not right after asking questions. I do have good 3 speed crank for sale if you wind up needing one. PM me.
 

Here is the ad I got it from, I think it is one I got (It is the Malaysia one). After I got it I measured dimensions and it was a short rod like the old one, the bearings were the same diameter as well. The overall length from thread to thread was the same as the old one but idk.
 
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Gary

Well-Known Member
Try measuring here and see if they are different. These are the engines that use the different cranks-CL70 SL70 XL70 don't know why they include all the models together because the others are different. I'll try to dig through my pile and measure them
 

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OLD CT

Well-Known Member
My crystal ball was correct. Malaysia crank. It's not for a 3 speed. They say it fits every ct70 LOL! Looks like the longer 4 speed version in the picture. The 3 speed version is not as long in the section gary shows in his picture. You have been duped... Malaysia ebay sellers do not sell/have the 3 speed ''discontinued'' cranks.
 

Robert thran

Well-Known Member
You could buy an advanceing style complete stator and flywheel ( to match your new crank) if you don’t want to tear your motor back down but there not cheap..but it might run better.?
 

Gary

Well-Known Member
I went to check today and found I have no 3 speed cranks that aren't already in something. But I did find a old picture from kirrbby that shows the difference-
 

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kirrbby

Well-Known Member
In the link you posted, the seller states...
"Just mention your model and year,then I will ship to you. Low price with high quality and absolutely original from Honda."
But I agree with everyone above...it looks like a 4speed type crank. Measuring from the face of the gear, the 3speed is about 2³/¹⁶". The 4speed is closer to 2½".
The 4speed crank CAN work, if you use a matching stator and flywheel...and as Robert said, it might run better if you use the advancing flywheel. But it will take your bike/engine AWAY from stock...if that matters to you. But if you really just want to get your bike back up and running...you have a couple/few different options of how to do that.

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Gary

Well-Known Member
Got me thinking which can be dangerous but I wonder that since the crank is wider on the 4 speed how did they keep the width of the engine the same? If it was wider the left side cover of a 3 speed would not fit a 4 speed. Wonder if the cover is actually made to fit the 4 speed and was used on all motors or does the flywheel and stator of the 4 speed sit deeper into the motor? Maybe this question is best left until winter when we all are bored and got nothing better to do ;)
 

OLD CT

Well-Known Member
It's either differences in flywheel specs or there is enough room under the flywheel cover for both correctly matched types. Giving the 4 speed setup a little less room under the cover.
 
Thank you guys for all of the information, I got the puller for the flywheel yesterday and will do the measuring, though I believe you are right about the crank being to long...
 
Also, if I may ask, what are the other ways to get it going? Would that be the 4 speed stator and flywheel?

I do want to get my bike running and don't really care to take it away from original if it makes it run better...
 
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Robert thran

Well-Known Member
Yes that’s the easiest way..maybe not the cheapest way..I think datv sells the complete stator and flywheel for the Mitsubishi style that will work but its Chinese made so I’m not sure how good it really is. Your other option is buy good used parts on eBay just make sure it’s all Mitsubishi or hatichi. The stator brand has to match the flywheel brand. Honda used both..
 
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