stuck flywheel

[gurt]

I'm using the correct kawasaki flywheel puller for my 89 kdx200, but I cannot get it to come free. I sprayed some pb blaster on the shaft, but it didn't seem to do anything. I tried using an air gun but that didnt work either. When I use a ratchet, I feel like I'm about to snap the end of the crank off it's on there that tight. Has anyone else had this problem or any ideas on what I can do? Thanks.

 

[reepicheep]

I had to pop the stator bell off a KLR-250, which I think was a similar problem... and it was stupid tight. I used lots of heat to get it to expand and loosen the grip...

 

[dirt bike dave]

Soak it very well with the pb blaster or liquid wrench, and let it soak overnight (maybe lay the bike on its side to get better penetration).

Get it under tension with the flywheel puller, and try tapping the flywheel with a rubber mallet. You don't want to smack the flywheel with a hammer or too hard, because you can break the magnets loose.

I like the heat idea, too, but be careful - you do't want to melt any wiring or the glue that holds the magnets on. I guess setting it out in the hot sun for a few hours might help a little.

Unfortunately, it is normal for them to feel like they are welded on. Especially on a 20 year old bike.

I had to pull the flywheel on my old '84 back in the day, and I could not beleive how much force it took. When it broke loose, it was loud and sounded horrible - like the flywheel was shattering. But luckily, no broken parts.

You are going to need a lot of torque on the puller - good luck!

 

[gurt]

thanks for the tips guys. I'll try putting it on its side and letting the pb just soak in. I tried the tension and mallet trick but that didn't work either. I'm leary about heating it up too much so I'll save that for last. The aggrevating thing about it is the bike was running fine this moring and I had someone coming to buy it. When I went to start it up before the guy came, it magically lost its spark :bang: . I guess thats just how this stuff goes.

 

[dirt bike dave]

Make sure your kill switch is working properly and not stuck.

In my experience, when the stator goes bad, it is more of a gradual problem.

 

[gurt]

That shouldn't be a problem for me lol. This bike hasn't had a killswitch for like 15 years. I wasn't the one who took it off, but I never got around to putting one on either.

I put the bike on its side last night and filled it up with pb and put the puller on keep some tension on it. I'll see if I can get it off after work and let you guys know what happens.

My guess is im going to need to sand the flywheel as the outside is fairly corroded and the cover apparently didn't have the best seal. The flywheel, stator, and cdi are all only a few years old on this bike so I can't imagine that being an issue.

 

[gurt]

Still a no go. I put a breaker bar on the puller, and its just destroying the cup piece on the inside. I'm really not wanting to heat the thing up because im afraid of burning up either the magnets or the stator.

 

[reepicheep]

All wire insulation and semiconductors ought to be able to handle 140 degrees F with no damage. And most will probably go closer to 190 with no damage. So just don't over heat it and you should be fine, and a little heat (and a few heat cycles) can go a long way to help.

 

[gurt]

How about whatever holds the magnets to the actual flywheel? Is that pretty tough stuff? I'm using a little propane torch but its still hard to direct the heat right in the shaft area.

 

[reepicheep]

I'm guessing that whole area is pushing 170 degrees when the bike is running... You want to heat the flywheel, not the shaft. The thermal cycles will help get penetrating oil in there as well...

And tap it a lot while it is under strong tension... again, don't whack it with a metal hammer or you could break off the magnets... but a plastic mallet or a hammer on a piece of wood ought to help.

On my KLR-250, I didn't use the factory tool... I used a flywheel puller I machined down to just fit... it bent the heavy puller, it was that hard to get off...

 

[gurt]

success! I heated that m f er until my puller was sloppy on the threads. At first it didn't work, so I went for broke, pulled out the breaker bar, wooden mallet, and the oxy acetylene torch and used them all pretty much at once. It made a horrible crunch/ pop broken crankshaft noise and then came off! Thanks to everyone for the advice. :cool:

 

[reepicheep]

That was my experience as well... it didn't feel like it came off so much as it felt like it exploded. I thought for sure the crank was toast.