chris_sims1981 Posted March 26, 2014 Report Posted March 26, 2014 I bought my banshee over the summer knowing that it needed a rebuild. I got new jugs that have been sent out for porting and a vito's 68 mm bore with standard pin location. After the install I found out that the piston petrudes the cylinders by about a 1/4 inch or so. Pic attached Quote
chris_sims1981 Posted March 26, 2014 Author Report Posted March 26, 2014 th rod has the yamaha engravement but I have no clue otherwise because the guy I bought it from didn't say it was stroked at all and I no longer have his contact info Quote
n2otoofast4u Posted March 26, 2014 Report Posted March 26, 2014 If it's truly stock stroke with 110 rods I'd measure the cylds and be sure they are correct height, then I'd measure the deck of the cases. What is the part number on the pistons? Set a bridge up off the studs and measure the stroke. 1 Quote
chris_sims1981 Posted March 26, 2014 Author Report Posted March 26, 2014 the location on the original pistons when i bought it were higher than the vito's piston. The cylinders were 5" and the case deck is 2 1/2" to the top of the base to the bottom of the jug " The vitos's part #V96870M68 and its about 1/8" or so tler than the piston that came in it which have the markings 8590H, 8963 and 69.95mm. Quote
chris_sims1981 Posted March 26, 2014 Author Report Posted March 26, 2014 should I get a spacer to compensate? Quote
n2otoofast4u Posted March 26, 2014 Report Posted March 26, 2014 You should measure the stroke before you do anything 1 Quote
Starwriter Posted March 26, 2014 Report Posted March 26, 2014 And figure out the rod length. Stock rods don't have an "engravement". 1 Quote
BANSHEE HP Posted March 26, 2014 Report Posted March 26, 2014 FYI stock cylinder height is 4.036/7" 1 Quote
sstaton1983 Posted March 26, 2014 Report Posted March 26, 2014 should I get a spacer to compensate? that will move all of your port timings up. You need to find out what you have before throwing shit at it. 1 Quote
chris_sims1981 Posted March 30, 2014 Author Report Posted March 30, 2014 sold the top end kit going with a Young Guns Racing top end build as soon as I recieve the new jugs. Thanks with the help guys! Quote
Starwriter Posted March 30, 2014 Report Posted March 30, 2014 Did you figure out the stroke and rod length? Quote
chris_sims1981 Posted March 31, 2014 Author Report Posted March 31, 2014 this is how i measured the crank and its 11 cm Quote
chris_sims1981 Posted March 31, 2014 Author Report Posted March 31, 2014 How do I measure the stroke? Engine builder said he can tell by the piston pin location to be sure. He will be recieving all my old stuff as well as the new jugs when I recieve them for the rebuild Quote
Starwriter Posted March 31, 2014 Report Posted March 31, 2014 Rod length needs to be measured center of crank pin to center of wrist pin. Tough to do when bottom end is still together. Easier to just go by the number on the rod. There is no way the builder can tell you the stroke from the pin location in the piston. You really need to measure the stroke. As Greene mentioned, put a plate on top of the cylinder studs. Measure from the plate to the piston at TDC. Then measure from the plate to the piston at BDC. The difference is your stroke. If all that is confusing, ship the whole motor to a builder. Quote
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