Gas Gas Flywheel Puller?

[Mr. Neutron]

By any chance, would anybody out there happen to have a flywheel puller for a 2010 Gas Gas 280 Pro? I'm told the threads are M27 X 1.0 (RH).

You can find those pullers with LH 27mm threads, for Suzuki & other Japanes mx bikes, but Gas Gas has right hand thread on theirs.....

I'd like to put a flywheel weight on my 280, and need to remove the stock flywheel to drill & tap 2 holes in it..... Was wondering if anyone might have the right puller a guy could borrow for a very short while?

Thanks!
Jimmie

[Sideup]

I have a gg flywheel puller.  I know it works for 2003.   It may work for you. Maybe one of the other club guys will know if it fits.
Do you have to pull the flywheel to add a weight?  Not familiar will that type.

Jack

[Mr. Neutron]

Hey, Jack!!!

Merry Christmas to ya!    Thanks for the reply!

Yeah, I bought Kirk's Hebo brand flywheel weight from him. The Hebos mount differently from the S3 brand FWWs. The Hebo FWWs need to have two holes drilled in the stock Gas Gas flywheel, and then these holes get tapped/threaded. You use the Hebo flywheel weight for the "template" for locating these two holes, and then they provide countersink head screws to help hold their FWW on. The flywheel needs to be off when drilling & tapping; you probably won't do any good to the coils & ignition electronics under the flywheel by drilling into those, hee hee......

I would guess that your flywheel puller for an '03 would work. The Hebo kit works on Gas Gas Pro models from 2002 thru at least 2012 model years.

I'm wanting this flywheel weight to help make the engine start a little easier. I've put heavier flywheels and/or flywheel weights on other bikes, and a side benefit has been that the extra mass of the heavier flywheel would let a tired, half-hearted poke at the kickstart lever get the motor spinnin' enough to start. I'm also planning on getting a low compression combustion chamber insert thingie (technical term there, ha ha) to further aid in starting.

All this is because I'm getting a replacent right knee joint in a few weeks. I want to make it easier on the new parts when kicking over the bike. I'd think about just buying a Beta with that left sided kicker, but my left knee needs some new parts also! I will probably be donating my old knee parts to the "kneedy", hee hee..... (Sorry.... I couldn't resist that....)

Jimmie

Adde in EDIT: The outside threads on the puller need to be RH 27mm X 1.0 pitch. 27mm is really close to an inch and one-sixteenth.

[Mr. Neutron]

Got the stock Gas Gas Flywheel off with the puller, Jack! It worked GREAT!!!!

Thanks a Ton!!!!

Merry Christmas to everybody here, & Happy New Year!!

Jimmie Newton

[Brian Clarke]

Jimmie
The best way to make the kick a little easer is to stack a couple of base gaskets under the Cylinder. You can easily get away with a couple of the thickest ones they make without causing cooling problems to the bike. Any more than about three than you start to lose the ability for the engine cases to work as a heat sink.
   Gas Gas also makes an Aluminum head spacer that I have used a couple of times that works real well.

[Mr. Neutron]

Hey, Brian!!!

Thanks for replying here! I appreciate that, and tend to listen when You talk about mechanicals on these trials machines.

The flywheel is on, and I think I'm gonna like it. In my "Deathly-Slow Tight Turn" deal I do in a patch of slick clay on my property, it seemed to work well. I didn't kill the bike in my short half hour ride I did yesterday. One thing I did notice was when revving the bike up to clean it out, it took about 2 weeks to wind down.....

Brian, I considered the gasket stacking deal you mentioned as a way to lower compression, and the head spacer as well. I then found out that I have an S3 head on this bike, and there are low-compression combution chamber "inserts" available for my bike, and ordered one of those last week. To my feeble mind, it just seems like changing an insert in the head would be THE most sanitary and/or reliable way to go about lowering compression.  A little more expensive, obviously, but no worries of gaskets leaking, or etc.. As long as I don't screw up an O-ring or something else in the process of installing it........ 

One thing I've wondered about here, and might be cool to discuss..... In the 70s, when people wanted more power from a 2-stroke, one thing folks would do would be to "port" the cylinder. Normally, this  involved enlarging, reshaping, smoothing, and God-knows-what-all of the transfer ports and the exhaust port. Typically, if the exhaust port got raised, it was anywhere from a few thousandths of an inch, to maybe a millimeter, to have more exhaust "port-open" time/duration. One thing this almost always did is make the bike a little "pipier", or move most of the bike's power up higher in the rev range. I wonder if stacking gaskets would have a similar effect? It would indeed raise the exhaust port slightly, which changes port timing. I'd bet it would hardly be enough to be noticeable, but has anyone here done this, and if so, what did you notice?

Jimmie