Hi Guys,
been some time since Ive been on the forum. back now wit another project!

yesterday I scored a szr 660 yammy. I dont know much about these bikes but hope to find out more as I go along.

apparently they were only released for 2 yrs up to 99. they have a 5 valve xt660 engine same as in the mz660 mastif & maybe the raptor 660 quad bike and the tenere 660.

It's liquid cooled and has a huge oiltank strapped to the front lower left side of the engine.

These are made by Belgarda italy and have paoli USD forks, brembo brakes and are reknowned for excellent handling (well, according to the info i got online).

the actual bike isnt in bad condition, but I just cant wait to start changing things around! To start with I'll loose the ugly pipe and fit a spare akrapovic to it that I had on a ducati.

Tonight I dropped off the cheap looking turn signals and fitted LED units to it.

Only problem is it has 64,000kms on it and I think the rings are shot. Its burning a little smoke and the engines a little worn sounding.

what I hope to do is stroke it and slap in a bigger piston to bring it up to 720cc (info found online). This will give it a new set of rings and some more power, I'll do the bearings at the same time.

has anyone had any experience with performance mods on these engines? any advice appreciated!

another plan was to keep my eyes open for a damaged xt660 r/x/z at the auctions and do a full xt660r engine swap (EFI and all, loom, dash, etc etc...)... but they are few and far between and auctions get top dollar for them.


the main thing was making sure the tank and airfilters are able to be fitted into the szr frame.
the 660r has efi and the tank may need a fuel pump fitted inside it (or would an external pump be more advisable?).

ok, another question... I have a wrecked xt660r frame, ECU, loom, airfilter & throttle body thats doing nothing. Im toying with the idea of fitting the 660R loom etc to the earlier 5 valve engine. has anyone heard of anyone doing this? One thing is you would need to make a manifold to split the single round throat into two intake tubes to mount to the earlier model head.

One thing that had me wondering was there was a sensor Ive saved that bolted into the gearbox. I dont know what this was. maybe some kind if a knock sensor or crank angle sensor or something. could this be just left out or is it an integral part of the tuning?

the bike is fun to ride but would suit someone shorter as my knees are too big for the tank cutouts! either way, Im dying to get it out on the twisty bits!

i hope i put this in the correct section, admins welcome to move it or edit if needed.

any input into these bikes would be greatly appreciated!