750/ 850

[speedo1]

I've searched, but, still no conclusive info. The 850 top-end on my 750 bottom, what kind of power output? Is it noticable to be worth it, or, should I just beat my 750 til' it blows up? \\/Anyone had success with this mod.?

[speedo1]

Wow!! 40 views and no response. I can't believe no-one has done this. After all. this is where I read someone suggesting this.Hmmmmmmmm.[-o<

[Tarbash 27]

I would think if you took your 750 cylinders and bored them to 844 so you have a fresh bore and got the wiseco 844 kit. Thats 10.25-1 compression compared to 9-1 stock. Yes Im sure there would be a difference. If you got the 80-82 gs850 head that had larger intake ports, and you put a bigger set of carbs on. Than yes, I can see some perfromance improvements.

[speedo1]

Yes, the Wiseco Kit would be an improvement. Someone suggested a more economical way is the stock 850 pistons in a bored 750 cylinder, that would free up money to have the 750 head worked on. It's almost $600 for the Wiseco Kit. So, I was just looking for anyone who has gone this route.

[fat_sac]

Yes, the Wiseco Kit would be an improvement. Someone suggested a more economical way is the stock 850 pistons in a bored 750 cylinder, that would free up money to have the 750 head worked on. It's almost $600 for the Wiseco Kit. So, I was just looking for anyone who has gone this route.

My dad kept talking about this for a while and saying that it was totally possible even to bolt up the 1100 jugs and heads. I never tried it and still don't know if it will work b/c I never found any info on it so I left my 750 alone.

[courier11sec]

My dad kept talking about this for a while and saying that it was totally possible even to bolt up the 1100 jugs and heads. I never tried it and still don't know if it will work b/c I never found any info on it so I left my 750 alone.

Totally off topic, but on your signature...
Looks like a neat product, but if I'm ever out fishing in a small boat and someone gets anywhere near me with one of those, I'll pop it.

[emjay]

Interesting, someone once told me that that's exactly what an 850 motor is - a 750 bottom with a larger top end. If that's the case, just put a complete 850 motor in there.

[speedo1]

850's are all shafties, no??

[emjay]

850's are all shafties, no??

Yeah, so maybe it wouldn't work out, seeing how the transmission is integrated with the engine. Someone else here might know for sure.

[49er]

Interesting, someone once told me that that's exactly what an 850 motor is - a 750 bottom with a larger top end. If that's the case, just put a complete 850 motor in there.

You can fit a set of 850 barrels and head on your 750. You will need to relieve the top of your crankcase to accomodate the greater OD of the barrels though. They provide a 3mm wall thicknes in stock form, the same as your 750 barrels. You will be increasing the bores from 65 to 69mm.
If you were to use your barrels and fit 850 pistons, your wall thickness will only be 1mm, IMO way too thin. You will get distortion of the bores under high loads and inadequate cooling of your piston crowns through the top rings.