Engine rebuild

[gerharddvs]

[dgyver]

The top end can be serviced with the motor in the frame. The case do not need to be split. The cylinders can be bored up to 5mm over but 79mm pistons are next to impossible to get. 78mm pistons are easy to get from Wiseco. They are made for the GPZ. I have a thread on this.

[gerharddvs]

Do you mean 5mm oversize or 0.5mm ? (What is the size on the standard Suzuki pistons ?
Are the GPZ pistons cheaper then the Suzuki since (the suzuki price is rediculas))
Can you give me more specs on those GPZ pistons so I can see if I can't find them from the dealers in South Africa ?
Where is this thread you were refering to ?(can't find it)

[The Buddha]

He meant 5 mm ... not 1/2 mm ...
Its a massive bore and port job he's talking about ...
In your case ...
140 isn't bad for compression ... the reason you get 180 when you put in oil is the fact that you're taking up space with oil ... OK a cylinder is like 243 cc at the bottom of the stroke, your compression is 9:1, so you are squishing it to about 28cc. A spoon of oil will easily be over 8-10 cc. That volume is going to be sitting in the chamber when you try to crank it ... no question the volume will be taken up by it and your compression shoots up ...
You want a 1/2 mm over bore. The re hone and stock piston and new rings wont do. Your old piston will probably have ring lands that are pretty much shot (indicated by the oil use) You'd either have to get stock new pistons and hone and fit it, or get a 1/2 mm over piston and ring set and bore and fit it. You're prolly better off doing valves and cams and the whole head at that same time. Wear and its performance impact is much worse with the head. I'd put new valves, seats, springs, guides (suzuki guides are trash), seals and check cams for wear (cos they are an easier item to fix later) and fit all of that into the head. They are all available as 1 kit from kibblewhite. Costs just a shade more than buying a set of valves from suzuki. Then of course piston and rings, hand fit the rings to the bores with new pins and clips. Just did it all with a eli 900. OK head I used a concourse head with 5K miles ... but the rest I had my guys do it a few weeks ago.
Cool.
Srinath.

[bcutrufelli]

can you document this process as you go through it with a digital camera?  I know its alot to ask but I know alot of people want to try this and would like to see a good write up

[dgyver]

Do you mean 5mm oversize or 0.5mm ? (What is the size on the standard Suzuki pistons ?
Are the GPZ pistons cheaper then the Suzuki since (the suzuki price is rediculas))
Can you give me more specs on those GPZ pistons so I can see if I can't find them from the dealers in South Africa ?
Where is this thread you were refering to ?(can't find it)

http://gstwins.com/forum/viewtopic.php?t=14401

[nisus1]

yeah, please document if you can... planning on doing this during the winter.

Thanx

[gerharddvs]

[500rider]

How much would a replacement engine with lower kms on it cost?

I'm thinking it may be cheaper/less time consuming. Then rebuild the other at your leisure or sell the cases etc on eBay.

[gerharddvs]

I can get a 2nd hand one for +-$1000 but "apparently" they don't know how many miles on the clock cause the front-end was smashed. (not worth the risk)

[davipu]

spliting the cases takes but a couple hours if you have a manual, just go step by step. I found when rebuilding my motor the factoryy manual was the best, had lots of pictures, and had basicly broken it down to which bolt goes whare.   1000 bucks for a used motor, no way man.   yes you can re-sleve the cyl.  but it's probably not worth your time, and the over sized pistons are probably going to be your cheepest route.