new oversized piston

79vwrabbit · Post by **79vwrabbit** » Thu Jan 17, 2008 10:25 pm

Hi, this is my first post on this forum. I browsed for a few days here and other places and haven't found an answer to my question. Here goes...I have an '85 Spree that I've been working on; doing some porting and grinding hoping to let it live another life this year. My barrel needs bored badly, but I ran into a problem when trying to order a .50mm oversized piston from Honda-they have been discontinued, and I found out only after I had ordered everything. I got the rings for the piston, rod bearing and pin and such, but no piston. The crankcase gasket is nonexistent too, but I have some gasket material and I can just make my own. I'm sure that somewhere there is a piston that will fit. You guys have probably encountered this situation already, and I'm curious what you did. There is surely a piston for another engine that will fit. Has anyone taken the time to find one?

uspmale · Post by **uspmale** » Thu Jan 17, 2008 10:34 pm

Here's the part #13107-GK8-306 PISTON (OS 0.50)

Try a couple of other dealers.

If that doesn't work, I have some used stock, honed and ported jugs available.

Kenny_McCormic · Post by **Kenny_McCormic** » Thu Jan 17, 2008 11:06 pm

There are some sellers on ebay selling overbore pistions for similar bikes, you might have luck there.

79vwrabbit · Post by **79vwrabbit** » Fri Jan 18, 2008 2:12 pm

I'm not so familiar with other scooters similar to the Spree, which ones should I be looking for? I think I'll also try to find a Wiseco or Pro-X or other aftermarket piston. I'll try to remember to let you guys know what I do.

79vwrabbit · Post by **79vwrabbit** » Tue Jan 29, 2008 12:40 pm

Alright, I have an update. It appears that the standard and 0.25 oversized pistons, along with the rings, can still be bought from Honda. I have a barrel from another engine that I was working on awhile ago that I am planning to use. I'm going to go ahead and get a new stock piston and rings and hone the cylinder (along with porting the exhaust, transfers and boost port and matching them to the cases). On a side note, the barrel I'll use is an '86 year with the factor hone marks still visible-not much running time at all, and plenty of life left. I'm still surprised, however that the .5 over pistons can't be found anywhere. Once I'm done, I'll try to post some pictures of my porting and what I've done to the cases too.

uspmale · Post by **uspmale** » Tue Jan 29, 2008 6:55 pm

Thanks for the update.
Looking forward to see results.

Kenny_McCormic · Post by **Kenny_McCormic** » Tue Jan 29, 2008 7:16 pm

Your gonna port and polish it all? That should turn out great.