Hi, I have an '89 CBR 600F and I want to rebuild the engine while I have it out of the bike. Does anyone know a good place to buy a rebuild kit preferably one with options such as compression ratio increase and larger pistons?

Thanks for your help

 

is your engine compression low? then get the cylinders honed and the pistons re-ringed. if you want larger pistons, then the cylinders can be be bored out (safely) to a combined 700cc. if you are looking for a short stroke engine, then that will require a talented engine builder. as far as i know, there isn't a kit out there off the shelf that has what you are asking for.

 

Thanks for the info Michigan_313.My bike has alot of miles and I thought it would be fun to bore it over a bit for a bit more power. Can anybody recomend a shop I can buy the larger pistons and rings from or that isable to do this type of work? Also, what performance gains can I expect from a 700cc engine?

Thanks

 

What are you calling alot of miles? And was it runnning weak prior? And google is your friend btw

 

The bike I have used to be my brothers and he drove through all of the lower 48 states and most of the Canadian Territories on a raod trip and was his daily driver for years needless to say upkeep was not his priority besides oil and filter changes. It has just over 35,000 miles on it. It was laid down and the subframe is bent so I'm sending the frame to be straightened. Since the engine is out I just figured I would rebuild it so Ican get another 35,000 out of it, but anytime Ifix somethingI like to upgrade it since I'm already in there. The overbore sounds like a good way to go. I just need to find the kit or get thedimensions of the 700cc pistons so I can have them made. I have $2,000 dollars to put intothe bike so Iplan on doing engine, suspension, and cosmetic upgrades. I know I can get a newer bike but I like having projects sothat's why I'm returning this biketo good condition.

Yeah, I'llstart googling now. I just wanted to see if anyone has had experience in this area before I jumped into it.

Thanks.

 

35k is all? thats nuttin for miles. My F4 has over 42k on it n runs like a top lol. Tho I do know where ya are coming from. I rather build a bike up myself than go buy the latest n greatest. No to mention I like the looks of my bike more than the newer ones lol. Good luck on your hunt for parts n you project in general.

 

I'd replace the timing chain and tensioner and call it good.

 

I think that's the way I'm gonna go for now. I did some searches and I couldn't even find an overbore kit. So, I guess I'll just do maintainence on it until the engine really goes. Thanks everbody for yourinput.

 

as i said before, there aren't any "kits". it's the same with cars that aren't being worked on for high performance gains. an engine rebuild shop will be able to source the parts you need. at the shop i used to work at, we did it all the time. people bring an engine in to get rebuilt and so they need a bore job to put the cylinder back into round. that means the cylinder dia increased and would need the next size piston and rings. and so we source from the catalog and were done. bike engines are no different. so long as the wrist pin dia is the same, there are many piston dia sizes made.

if you want to bore the cylinders out, call around to engine rebuild shops and ask what they would charge for bore increase, piston, and rings. there's gotta be at least a couple of shops that have done motorcycle heads and cylinders. think of it this way, when an old bike goes to the dealership and they have to tear the engine down because the bike is high milage > 100,000 mi., and there is next to no compression because the rings and cylinder don't meet up, they have to send the cylinder and head out to be worked on. what i'm saying is, what shop does the dealership use for that kind of work because they don't do it in-house.

call up a dealership and ask "hey guys, where do you send your cylinder and head work to?". if they are nice, they will tell you.

the rebuild shop will also be able to determine how much to take out for 700cc or whatever so long as the walls don't become overly thin. if it were me, i would go to 650 and leave some meat in the walls. you can always go bigger next time or whatever, but if you blow out or crack the cylinder wall going to big, you may not be able to get it resleeved. i don't remember if there is enough webbing for a resleeve on the 87-90 cylinders.

 

Thanks michigan_313. That info helps a ton. I think I'll wait until it definetly needs to be rebuilt and focus on suspension and cosmetic mods for now. It's awesome to hear from someone with experience on this topic and I will definetly heed your advice. Thanks again!