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03 R1 engine rebuild

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16K views 23 replies 7 participants last post by  Yogiroo  
#1 · (Edited)
rebuilding my 03, looking for a bit more power and more torque and want some advice... targeting around the 180hp mark if i can do it semi reliably.....

actually i'll just list the spec i'm looking at and let people pick holes in it :)

i'm looking at doing a 1mm overbore (2mm is max and requires a resleeve i believe?) looking at a JE piston (13:1 ratio) kit to suit or maybe wiseco? cost isn't a big problem here, but CP pistons don't seem to have a listing for the 02/03's.

cometic spring steel head gasket

graves intake cam with new graves springs and new valves.

exhaust match porting, 5 angle valve job (if i can find anyone in Queensland Australia who can do it well)

milled head to increase the compression a bit (not sure how much as i need to check the clearance once i decide on the crank/pistons)

YEC ECU

ram air (boxr or graves)

balanced crank/rods/pistons

maybe a 4mm stroke increase as well (in which case i hope to get some carrillo rods) -or if i can afford it an APE or Graves stroker crank.

(i realise the stroker crank will reduce big end bearing longevity etc)

uprate the gearbox to take the extra load (back cut gear dogs, undercut gears etc etc)

one big question is this, if i do a 1mm overbore (or 2mm with a new sleeve), do i then have to recoat the sleeves with nickasil ? (or whatever yamaha call it)
 
#4 ·
If you haven't gotten any info yet I'd call APE or Graves direct. Graves has a section here too and I know Taige is great on getting back to people.

APE just moved to Palmdale from here in Burbank and they've always been great to work with... they built a new place from the ground up at WSIR. Looks too modern compaired to all the old knowledge they have! :lol
 
#5 ·
Already tried APE and then reconfirmed with some of the older members here. Gonna have APE increase to 4mm. Then add Carrilo rods but will stick with stock pistons and bore. So this'll increase engine from 998cc to 1067cc. :thumbup Bill is gonna be around 2k... :crash
 
#7 · (Edited)
Already tried APE and then reconfirmed with some of the older members here. Gonna have APE increase to 4mm. Then add Carrilo rods but will stick with stock pistons and bore. So this'll increase engine from 998cc to 1067cc. :thumbup Bill is gonna be around 2k... :crash
Nice! :D

I'm more than happy with the 141hp I get from my pretty much stock 02 in the middle of summer heat. I'll never ride it over 95% of what it can do on the street. It would just get me in trouble!

I'd rather put the money into making it stick to the road and more of a joy to ride. Upgrading the brakes, front fork internals, rear shock, and setting it all up made it more fun to ride and makes people on newer bikes wonder how my old horse keeps up with them!

But ya gotta do whacha gotta do! :hammer:
 
#6 ·
i am in the same sort of situation only a lil worse. i have 32000 miles and dyno # came in at 123hp and 64 torque. I spoke with my area's official/un-official moto mechanic guru and he told me for around 1500 he would freshin the motor up which included a basic over haul new rings seals and all the stuff that would bring it back to stock specs. and told me for about 2200 he would rebuild the motor w/ cams and pistons and the works. said that the bike would out ride any new liter bike? now my concern is, is that price worth it? and is that really possible for a 2003 motor built to handle that much hp increase and last or will i probably have the issue of once he starts i'll have to upgrade this to work with that and so on.??

your $0.02 wanted!
 
#9 ·
My project is pretty much done. I have a long list of details of what I done to mine. I'll write them down for you. I have spares for my bike so if any of you are interested let me know. I have a YEC High lift intake cam, YEC race harness, YEC springs, YEC head gaskets all for the 02/03 R1. I have part numbers also on them so if you want to look them up.
 
#10 ·
My project is pretty much done. I have a long list of details of what I done to mine. I'll write them down for you. I have spares for my bike so if any of you are interested let me know. I have a YEC High lift intake cam, YEC race harness, YEC springs, YEC head gaskets all for the 02/03 R1. I have part numbers also on them so if you want to look them up.
let me know when you put them up for sale. Definitely interested in the intake cam.
 
#19 · (Edited)
lots but you need to understand that when you start getting into the engine, you've already exhausted the normal (relatively cheap) mods like exhaust, v-stacks, blockoffs, Power Commander, wheels, etc etc...


And it gets VERY expensive... :fact
 
#21 ·
yup... a good engine/headwork will cost as much in labor as in parts almost if not more than a complete bike. But if you can get 180-200hp out of a 98-03 motor. :rock: