Thread: Renewing an SL70 Clutch Question

I traded 2 - 12 volt / 7AH fire alarm batteries for an SL 70. (Frame #SL70 1077595 / Engine #CT70E 201031.

The engine seems to have a 3-sp transmisson, right?

It has the semi - auto clutch that needs to be rebuilt or replaced. (Just like everything else on the bike. More about that later.)

I'm building this bike for my 2 young nephews, ages 12 and 9.

Should I rebuilt this or replace it with an after market assembly?

Any thoughts about converting to a manual? These children have never ridden a motorcycle before.

Post a picture of the bike.

Your engine is from a 1971 3speed CT70 KO...Maybe the clutch just needs adjusting. If it's a bike to learn on, leave that motor in it while you look for the correct engine if you are going to restore it.

Thanks for the reply.

The clutch plates are rusted and will need to be replaced. I thought it might better to get an aftermarket assembly, if they're any good.

It's not my intention to restore the bike. I'll leave that to the nephews. My plan is to get it running so that it can be safely ridden.

Did the bike set outside with the cover off for some time? It's kinda odd that the plates are rusted when they should be running in oil. Or did the engine get water inside at some point? If so if you have rust in other parts of the eng. ie, the rod bearings or crank main bearings when you get it started it might not last very long. If it just had the cover off for some time you might get away with just rebuilding the clutch. the stock clutch will be fine with new plates and springs.MHO

I don't know the history.

I removed the head and cylinder. The rings were broken but the bore looks good. It measures 1.852 inches. The inside of the engine doesn't look rusty. No rust on any of the steel parts. I guessing it sat with no oil in the primary.

I'll do a top end, replace the cam chain and replace the carb. I have new coils for the electrics and ignition.

I'll probably spent more on the engine than a Lifan would cost. Maybe I should just get a Lifan

Originally Posted by stuck amals

I'll probably spent more on the engine than a Lifan would cost. Maybe I should just get a Lifan

I would rebuild the Honda...But if you do get a Lifan, I would follow the break in procedures on it closely. Check it over carefully before starting and drain the oil that comes with it. Drain the oil after every 40 miles of use for the first 200 and check for metal particles. If you do get a China motor, buy from an established dealer like dratv, pitster or mytrailbudy...don't get one from a new seller on ebay...There is a good chance you will need support and those vendors have that along with wiring diagrams. You will have to decide on 12v or 6v.

There have been good and bad experiences with the Lifan's and all the Chinese replica's. I just got my first Lifan Replica bike a few weeks ago and the original owner had been following the break in procedures...This bike only had 122.9 miles on it. The Lifan does seem to be one of the most reliable of the China motors according to what I have read.

You can read what I have found so far in my thread about it. The first page is the only one that talks about the motor. I got lucky, so far. Also, read what others here have experienced in the Chinese threads on this site. Those posts are very informative for anyone thinking about buying a clone.

Sounds like you said, sat with no oil in the primary. If you go with a Lifan I agree with what karen said, change the oil often and check for shaving. I have a Lifan in a bike and have good luck with it. But Its noisier then a Honda when idleing in netural. they don't shift as smooth, and I have had more wear then normal on my manual clutch cover release mechanism then normal. But for what you said you were going to with it I'd go with the honda. 2 clutch disc's are 15 bucks and springs are around $10 I think just clean it out put in new oil and your ready to go. since this is there first bike I'd leave it at 72cc, maybe hit the cyl. with a hone, new rings, new gaskets and seals and they will be riding in no time. Good luck, have fun.

Thanks for your opinions. I'm going to get this engine running and not go with the Lifan. I've cleaned it up a bit and took some pictures.

You'll see the carb is trashed but I think the intake is re-useable. It needs a little cleaning up and some fresh chrome and it's good to go!!!

Love the intake!

Where in the wide world of sports did you get that intake??? I love it. Hey that motor looks fine better then the ones I've got lately. the metal clutch disc's will clean up fine put in new fiber disc's and springs, get a new carb and it looks like it will run.