Wcrracing221

No problem. Engine builder measured 21 cc so thats the number I’ll trust.

Hi guys, Trying to order custom 771 pistons at 11:1 compression for my race bike. The piston manufacturer need the cc of the chambers. Anyone know the stock cc? Does 21 cc make sense? Thanks Dave

Hi Guys, Any source for overbore kit for short stroke 88-89 GSXR 750. Wiseco 771 or similar. Thanks in advance. Dave

I’m in the same boat. P4F1 class rules max 5% overbore. Planning Wiseco 771: undercut gears, Mikuni RS38SS carbs with 30 mm Velocity stacks, and Hindle Stainless exhaust.

The chain adjusters are the same as the 92 I chopped up. Are you saying this is not stock but rather modified?

You need to compress the front suspension to it’s limit to ensure the front wheel does not contact the cooler on heavy braking. Very important as wheel contact could cause catastrophic failure.

Hi all, Acquired a slingshot with an unidentified swingarm. Would like to move it to my 89 750 race bike. Can anyone identify year and model? Thanks

Oil coolers and venting.

Read the frankenstein posts and although can be done, sounds like the work does not support the benefits. I’m going to build the short stroke and if I need to change the oil pan and pickups, I can do that. The new motor will have Mikuni RS38SS carbs with matched ports and velocity stacks same as the current engine. Any other tricks?

Sudbury, Ont. Thanks Eh!

Hi all, Preparing to build a new motor for the race bike. 2 hour endurance plus 4 sprint races 20 and 30 minutes each per weekend. looking for 130 hp on premium pump gas and reliable. Bike has 2 aftermarket oil coolers, dual venting etc. I have an 89 short stroke and a California 92 longstroke as donor motors. i cannot use the 92 as it is not legal for my vintage. The plan is to undercut the gears and do a 771 Wiseco kit which keeps me legal. Question: Can I and should I use the bottom of the long stroke and the jugs head etc from the short stroke to make a frankenmotor? In theory this could increase the volume and open options for 4 into 1 exhaust over the rarer 4 into 2 into 1. Comments and advice appreciated.