Super Jet Turning a 760 into a 701

[IslandRider]

I bought a complete gp760 as a donor for its motor. (62t cases 64x top end) Im removed the 64x top end and I'm planing on putting a 61x top end on it and making it a 701. I'm using the stock carbs that came on the motor (mikuni 44s). Does anyone see any problems that I may run into? It seems like a common thing people do.

 

[DarkWater]

The 61x top end will bolt on nicely. Just be sure to use the proper head/ domes for the cylinder bore. Fresh gaskets, maybe some carb tuning and go.

 

[IslandRider]

The 61x top end will bolt on nicely. Just be sure to use the proper head/ domes for the cylinder bore. Fresh gaskets, maybe some carb tuning and go.

I'm going bore out the cylinders a half over stock and get pro-x pistons to match the size as well. The head I'm going with is an ada girdled head with 35 cc domes so I can run pump gas. Motor is completely broken down. I've spoke to jet maniac about gaskets. Just waiting on a couple of other things so I can put in a big order all at once.

Any problems with the manifold? I've heard that it doesn't work. Or maybe that's if I wanted to run 38s?

 

[DarkWater]

The cases are the same. Only difference is, the 760 cases are cut to accept larger sleeve and they will have a duel pulse line.
The cylinder doesn't effect the carbs.
The manifolds are different for the 38s ( 701) and the 44s (760) but both manifold set ups are interchangeable on the 62/63/64 cases
The bolts for the exhaust manifold are different sizes tho.... that may present an issue.

 

[Matt_E]

I bought a complete gp760 as a donor for its motor. (62t cases 64x top end) Im removed the 64x top end and I'm planing on putting a 61x top end on it and making it a 701. I'm using the stock carbs that came on the motor (mikuni 44s). Does anyone see any problems that I may run into? It seems like a common thing people do.

If you are using a stock head, use the 61X head.
If you are using a stock exhaust, use the 61X exhaust.
I recommend using the 701 ignition.

 

[r6487]

just curious why the downsize and not build your own version of the jetmaniac 781 big bore

 

[DarkWater]

↑Port timing↑

 

[waxhead]

Dont worry about it. Your wasting money. If you that concerend about it then remove base gasket and use three bond to seal it up so it drops it 1mm and recess cut the domes in the head.
Either that pump the compression up and it will go well