surfish95747 wrote
Thank you very much! That will save me some cash! Now I guess I can do the big bore kit. What is the difference between these kits and the Wiseco kits?
My '80 has Wiseco's in it. I think there may be different pistons available, but most of them are high compression. My jugs have a spacer under them to drop the compression so it will tolerate pump gas. Jug spacer also means custom length cam chain. Just added cost/fiddling that a street bike really doesn't need at all. But mainly, yep, you're paying for the name/reputation.
I'd have no fear going with the ebay pistons. When they come in, if you see a hunch of sharp edges, just smooth them over with some 600 grit and rock on.
You'll be surprised how well a 823 with 900 cams runs.
With stock gearing on 17'' tires I can hit 100mph in 3rd with ease.Once 3rd gear hits about 120 I back off. Never tried to go any faster. It won't rev and charge at upper rpm's like a modern sport bike will, but it will have torque down low that the new sport bikes aren't making at the same rpms/ cc's.
A stock 900F only had 8.8:1 compression. At 901 cc's it made an honest 95hp through stock exhaust. An 823 with decent compression, good exhaust and properly tuned carbs (stock jetting is horribly lean) will make that same power. Work on the head and you can make even more. I gave a early 00's ZX750 a run for his money one day. He was shocked I could hang with him...so was I!
Those bikes are about 20lbs lighter and spec'd around 120hp. Not to mention their aero advantages. When you keep the original torque and add hp it makes for a great running street engine.
Hey, while you are thinking about all this look into 900 rods. Much beefier pieces. With good valve springs they will allow you to turn the bike up past 10k rpm with confidence. I've taken mine to 12k many'a times. You might be able to get some 900 rods cheap off ebay.
Locked
Go ahead and build your bike now ( suspension,brakes,etc) and just pick up another set of jugs to borw when your budget allows.
