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For those wanting to keep their bike the way the factory made them.

Moderators: oldjapanesebikes, H2RICK, diamondj, Suzsmokeyallan

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Admin
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Post by Admin »

Yeah, I see 'em on eBay all the time too...unfortunately, they're almost never the 2nd oversize I need and frequently they're the newer style for the '76+ model years.

From the pics I've found of the '76+ pistons, there's never a view of the intake side to see if they have the intake ports or not...
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Post by Admin »

Admin
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Post by Admin »

Hmmmm....no ports....think it'll work if I can find a 2nd oversize?

I checked through Alpha Sports microfiche and the piston pins are different part numbers (between the '77 model year and '73 model year), but the pin bearings are the same???

I'm guessing the pin is shorter on the later models to accommodate the side cut-outs...
Admin
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Post by Admin »

Sure it wouldn't hurt to do some Comparing.I think those side Cutouts work as the boost ports though. :?
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Post by Admin »

jughead wrote:Sure it wouldn't hurt to do some Comparing.I think those side Cutouts work as the boost ports though. :?
I don't think so. Boost ports work better if they extend above the rings.


Lane
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Post by Admin »

Thanks Gabriel!

Phil C
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Post by Admin »

You must retard your iggy timing if you are running on stock gas or you risk pinking and holed pistons.

Phil C
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Post by Admin »

copper slip is just as good.
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GT 380 EXHAUST DECOKE?

Post by Admin »

HI THERE ,YOU'V PROBABLEY BEEN ASKED THIS A THOUSAND TIMES BUT WHICH IS BEST WAY TO DECOKE MY DIRTY MINGING PIPES,WITHOUT BLOWING MYSELFE UP?
Admin
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Post by Admin »

I done pipes first by hand, long screwdriver trough the intake tracts then I closed all the holes and filled with laquer thinner, revolved the piped from time to time in 24-36 hours... this is a job that you MUST do in open air. Others fills the pipes with backing soda.
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Post by Admin »

I just picked up a box full of NOS Suzuki pistons at the local dealer, I have several TS250 pistons and one 1mm over, PM me if you want it before I ebay it, no rings though.
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Post by Admin »

Phil C wrote:You must retard your iggy timing if you are running on stock gas or you risk pinking and holed pistons.

Phil C
Hmm...I wonder if that's what happened to my GT500(detonation). My heads were milled down a few thou by the p/o. I was running 92 octane, B7HS sparkplugs
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Post by Admin »

A few thou off the heads should not make much difference with stock timing but it is generally considered that increased CR with milled heads normally needs less advance unless you can get some higher octane gas.

I have seen 3.1/3.2 mm BTDC recommended timing for - 0.5mm heads but this will need some experimentation.

Phil C
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Post by Admin »

Spondon wrote:
Phil C wrote:You must retard your iggy timing if you are running on stock gas or you risk pinking and holed pistons.

Phil C
Hmm...I wonder if that's what happened to my GT500(detonation). My heads were milled down a few thou by the p/o. I was running 92 octane, B7HS sparkplugs

If it were that, it should have ruined them both. How does your other piston look? Of course, I'm assuming that both heads are the same.....


Lane
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Post by Admin »

Phil,

Thanks for the info and sorry for my ignorance, but whats CR?

Lane,

The other piston looks alright, in fact Scott Clough looked at it and said it'd be perfectly fine to re-use. There are pics of both pistons in the "2 strokes(street)" forum under the "thanks a lot CHP" thread
Yes, both heads are the same. Shaved down a bit
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