G1 big bore kits??

[slonomo]

Originally Posted by mikeasis

Slonomo any recommendations on a bigger carb that would fit the stock intake or carb and intake replacement.

I don't know of any stock replacement carb that is larger. Some guys have used Mikuni carbs but you have to rig it up with some aftermarket parts to get it to fit. The issue I had was space. Using adapters and pipe etc you tend to run out of room and the carb runs right into the transaxle. Maybe someone has done better.

Now on my Enticer 250 setup I used a Bravo 250 Kehin carb. It fit up fine.

There used to be a guy on here that put a Mikuni on his G1 215cc and got it to work well. He has since gone away and took all his pictures with him from all his posts. Otherwise I'd tell you to look at what he did.

[raydhd]

A lot of the dirt bikes,snowmobiles,and quads that are 250 cc use the mikuni VM 26. Maybe as large as VM 28. The 340 snowmobiles use a VM 30. My 440 uses a VM 34. The nice thing about the mikuni VM's they are very easy to tune and are relatively low priced.With plenty of parts support with needles and jets as well as being fairly compact. Safest bet is probably the VM 26. P.S. If you still have some of the harley/columbia 2 stroke carbs around I had the tillotson spinning my HD engine to 6500 rpms when the cooling fan said goodbye. Some members here are also using walbro carb on their marathon 2 strokers with great success.

[mikeasis]

It has arrived! Comparing to a first over NOS piston. It just doesn't look that much bigger lol. Waiting for the one piece I almost forgot, the wrist pin bearing.

[raydhd]

One thing to note is the compression height over the stock piston is very different along with the oil control ribbing at the lower part of the piston.

[dezrcr822]

Originally Posted by mikeasis

It has arrived! Comparing to a first over NOS piston. It just doesn't look that much bigger lol. Waiting for the one piece I almost forgot, the wrist pin bearing.

Are there any windows cut in the new piston? Also do they say what the large silver ring was for?

[mikeasis]

no sire no ports in the piston, the bottom of the piston skit was modified for that purpose. I assuming this changes port timing, what that means exactly I don't know.

I thought the plate may have been a shim for the bottom of the jug but I don't see it in the kit although I have yet to open the gasket set that came with it which I'm hoping the circlips are in there as well.

[slonomo]

I'm definitely not a 2 stroke expert, but this doesn't look anything like the stock setup. Obviously the ports on the jug must be different as well. I'd like to see the inside of the cylinder comparison as well. Anxious to see how this works out.

[mikeasis]

Im doing a complete rebuild and thought id post pics in my crank case separation post below.

http://www.buggiesgonewild.com/gas-y...acement-2.html

I really despise phillip headed bolts. Is it normal for a connecting rod to say ROCKET on it??

[jkenprice1]

I'm kinda ignorant here, butI thought the add said 1/2 of 1mm oversize. Isn't that standard over size. I don't know what the definition of a big bore kit is, but that doesn't seem to be one.

[mikeasis]

This kit is 2mm or .080. The biggest Yamaha ever offered was .040. and they have been discontinued for awhile now