I'd like to know if any of you have any tips relating to installing the 862cc jugs, heads, and pistons on the 02 800 EFI bottom end. (All stock AC stuff) I've seen posts on other sites that say it's just a bolt on and go deal. Who has actually done it, and how did it work out for you?

Thanks

Easy to do on a carbed 800 perhaps but where will you get the required extra fuel to run those extra ~100 CC's with your EFI system?
Also, you must use the ZR900 manifold and pipe( see e-bay). The ZR8 pipe is to tight on a ZR9. Watch the APV clearance as well. Are the APV parts identical on both models? Check Browns perhaps. The CDI is fine, in fact you'll be faster than a stock ZR9 if you stay with the ZR8 CDI but you may need to add an aftermarket harness to bump up the fuel.

Good Luck!

Huz Like I pm'ed you the timing between the 8-900 efi is only a degree at 7500 rpms 8-9 the biggest difference is in the fuel map and Maybe like the last post said the y pipe. I would think too a different pipe for a 900 would be a ++++ Joel

You can use the 800 valves if you make a shim washer equal to 1/2 the increase in bore size.

Thanks for the replies. I will have the APV guillotines for the 900 top end as well. I understand the 800 pipe is a little tighter. May not be an issue for me at 6k+ elevation all the time? I have a stock 900 pipe and can off a carbed 03 that I can use for testing. I also have the stock 800 EFI pipe and the D&D 800 single. Something's bound to work. I'll let you all know how it goes after the snow flies.