Thoughts on a advance/offset flywheel key for ATC70?

[Blown 331]

I'm considering trying an offset flywheel key to advance the timing on an ATC70. I was thinking of trying a flywheel off a hand clutch model which have advancable timing but I'd still have to drill the flywheel for the recoil cage and I think I would likely have to change the stator as well. I know advance keys were popular on 400EX's on top the the advancable timing they already have. Currently the only timing adjustment on a 70 is open the points gap. I usually run mine with the widest gap possible. It makes a huge difference on power. I haven't come across one for an ATC70 or clone engine but theres lots of offset keys out there. I'm sure I could make one work. Maybe this one. http://www.ebay.com/itm/190758404804?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649
What does everyone think? I searched the site and found no mention of this at all.

[Flyingw]

What have ya got to loose? I say give it a whirl.

[BigRed_Ryno]

can't you just advance it on the points?

[greenhuman]

Try a Honda SL/XL70 flywheel. They bolt straight on to the later, wide zip starter model ATC70,s. You should not have to change stators. The only work involved is attaching the cage which can be tacked welded on if you don't want to drill and tap. It will give a definate boost in performance.

[Blown 331]

can't you just advance it on the points?

Opening the point gap is the only way to advance timing. The points mount with pin that slips into the stator plate so theres no way to elongate a hole or anything like that either.


Try a Honda SL/XL70 flywheel. They bolt straight on to the later, wide zip starter model ATC70,s. You should not have to change stators. The only work involved is attaching the cage which can be tacked welded on if you don't want to drill and tap. It will give a definate boost in performance.

The reason I thought I might need to change the stator is some hand clutch flywheels are Mitsubishi and some are Hitachi, they are different. Even the stator backing plate is different.
I'll probably give the flywheel swap a try, I have plenty of them. I don't want to use all my good flywheels up on ATC70s plus one of my favorite one is a 3 speed with the narrow pull starter. I figured this key thing is cheaper and easier than flywheels. I've been meaning to measure a stock ATC70 flywheel key and compare it to this guys measurements but I haven't gotten around to it yet.

[greenhuman]

The thing is the advancing flywheel will advance later in the revs but keep the standard timing for torque. It will make more top end HP.

[BigRed_Ryno]

im not sure what flywheel it was i got for my one, it was one of the honda '70 models with the weighted advancer in it. I had to turn down the riveted on outer ring a little on a lathe for the pullstart cage to fit on, then I just tack welded it to the ring. it fitted straight onto the atc70 without having to change out the stator or anything. I timed it up with a strobe gun I cant remember how much it advances when revved etc... it doesnt give a huge power boost but certainly doesnt go as flat at high revs as quickly. definitly gives a slight edge over stock, but dont expect much