GOL single ring pistons

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Charles
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Post by Charles »

The pistons came in these boxes, but I can't find any type no.:

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If anyone else wants a set, just send me a pm. I only need one set for myself.

Charles
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JanBros
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Post by JanBros »

Charles wrote: They are the same height. I measured from top of gudgeon pin hole to dome of the piston.

Charles
then the top might be almost as high, but it's clear in the pics the sides are lower, so you needto reshape your head .

new problem when you do that : if you ever need new piston's, you have to know which ones these are, or have them specialy made which will cost a lot more.
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blanc
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Post by blanc »

pm sent
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mj43
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Post by mj43 »

That is a chunky piston is the ring pin at the back?

Piston Weights

What is the dome radius?
Charles
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Post by Charles »

Hi MJ,
mj43 wrote:That is a chunky piston is the ring pin at the back?
No, it's in the same position as the pin of the lower ring on the Mitakas:

Image
mj43 wrote:What is the dome radius?
Don't know to be honest, I'm currently asking the factory to identify the piston. Hope to get a reply soon.

Charles
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Post by blanc »

Looking forward to trying a set.
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Post by mj43 »

Charles thanks

It looks a good solid piston.

Will probably be ok for racing as the KR crank and rod are plenty strong. But given the extra weight I would try and limit peak RPM keep it down to 12,000 to 12,500 on the tacho (which is all you need anyway). I might try a set.

The TZ pistons I use are about 20g lighter and I do over rev occasionally to 13,000 ~ 13,500
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Post by blanc »

Thanks too. On the topic of piston weight, would a heavier piston weight generally indicate a longer life span for racing vs say a lighter tz piston?
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Post by mj43 »

It looks like a strong piston - I am not concerned about the piston it is the extra forces on the crank because of the extra weight. Cranks are scarce nowadays and I want mine to last as long as possible.

Depending on how serious you are about your racing piston life can be as little as 500 miles. I have got slack nowadays (not as competitive) and now do them once a season (about 1500 miles). I did run a set for just over two seasons once but broke a ring at the start of the third.

I start a season with new rings and change them mid season.

As I say they look a good piston and will be fine - as mentioned my try some myself.
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JanBros
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Post by JanBros »

mj43 wrote:as mentioned my try some myself.
you don't see a problem that the edge off the crown is lower (if you don't shape your head accordingly) ?

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Post by Luders »

Charles wrote:
mj43 wrote:What is the dome radius?
Don't know to be honest, I'm currently asking the factory to identify the piston. Hope to get a reply soon.

Charles
Have you heard back from them yet?
Charles
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Post by Charles »

Luders wrote:
Charles wrote:
mj43 wrote:What is the dome radius?
Don't know to be honest, I'm currently asking the factory to identify the piston. Hope to get a reply soon.

Charles
Have you heard back from them yet?
No not, yet. :? If I don't get a reply soon, I'll ask a mate who talks italian to contact them.
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