removing flywheel

I'm having some trouble removing the flywheel on my motobecane mobylette. In the manual it doesn't mention using a flywheel puller, since the flywheel is retained by a threaded cap with a square hole in the centre. It says to lock the flywheel by placing a bar through the connecting rod and support the bar with wood blocks, then use the stock from a 3/8 drive socket in the square hole of the cap. The cap is a left hand thread which i think means turning it clockwise to loosen it. Am I doing something wrong or is the cap just on really tight ? Can I use wd40 somehow to loosen it ? Any suggestions are appreciated.

Re: removing flywheel

It sounds like you are doing everything right.

I have not seen a left hand thread flywheel nut... But I have not worked on many Euro peds.

But if the manual says it is a left hand thread...then keep doing what you are doing... (clockwise)

If it doesn't want to budge... You could take it to a garage and have them use an air impact wrench.

Or you could try a hand impact with an adaptor (if needed).

Liquid Wrench is a good penetrant.

WD40 is not as good IMO... but its better than nothing.

Re: removing flywheel

The Moped WareHouse of New Jer /

You are doing it correctly. The nut is reverse thread and the square is slightly larger than a 3/8" ratchet, but the ratchet will work in a pinch. The part that you will need a puller for is the point cam which is a conical press fit onto the crank shaft. Depending on what your doing to the engine you may or may not have to even remove this though. Make sure that you inspect the flywheel and cam lineup dimples and that it is seated correctly when you reinstall the flywheel. . The flywheel nut is of a fairly soft alloy so try to avoid using the air impact gun on it. We do have new nuts in stock if you neeed one. Also a good way of removing items such as this if the engines top end is still intact is to feed a length of rope throug the spark plug hole and then rotate the piston to the top. The rope will prevent the engine from making a complete revolution.


The MopedWareHouse


gimmejimmie /

Hi Fred,

I thought you might have went to Bike Week for the Daytona 200, that's a helluva race to see live.


Re: removing flywheel

Thanks for the help, i'll use some liquid wrench or wd40 and keep trying.

Re: removing flywheel

Well, this thing won't budge. I guess I'll try the air impact wrench.

Re: removing flywheel

i got an interesting but semi dangerous answer. try to take the wrench and put it on the fly wheel and have a friend try to start the bike while u hold the wrench still. try that and see if it works.

Re: removing flywheel

Ron Brown /


Strike the last sugestion. The thread is left handed to prevent that from happening!

Use the impact, it worked on both of my motobecanes.


Re: removing flywheel

Thanks Ron, I'll use the air wrench. Now I think these come in 3/8" and 1/2" sizes, I'm assuming I need the 3/8" one. Thanks everyone.

Re: removing flywheel

Reeperette /

You could try what I did on the oil pan plug of a car once.

Those dillwads at the oil change shop slammed it on with an impact so that the owner would NEVER get it off, and I suspect that's rather deliberate of them.

Anyhows, I put a very strong, well-serving ratchet on it, and then got a long piece of tubing and slotted the end of the tubing over the ratchet handle, one holding it on, two more pushing the bar of tubing, we did get it off, and someone got a lecture about going to those damn quickie oil-change places the whole damn time.

But be careful, cause I suspect would could probably shear the bolt that way.


I Wish!

Yeah... I'm sure it is fantastic.

I would enjoy the whole week...all the races.

In fact 3 of my friends are going (or have already left).

Re: I Wish!

Ron Brown /


I am planning on riding down to spend next weekend there if the snow clears in time.

If I make it, I'll think of you.


Re: removing flywheel

frito bendito /

your gonna have to get a puller to get ur flywheel off because i had the same problem with my flywheel on my 80cc i just took it to my dads work and i got him to pull it off.

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