The reason a vmax4 didnt have case webbing is its a "cylinder reed engine"..... thats comparing a apple to a cucumber, totally differnt engine design. A redhead is a fair comparison case wise to a srx/viper engine, its a case reed engine, however your dealing with a differnt stroke and cylinder design.
the webbing is all about packing the case and controlling the velocity up thru the transfer ports, yamaha evidently felt the need to use it in the srx/viper engines to take control of packing the case. It was surely needed for the srx600 engine as the piston is very small for the case/port design, seen lots of differances when modding that engine.
engines with the webbing cut out will increase case volume, but if your not needing that case volume increase, would actually lose pumping effiency, not the other way around.
opended up cases work well with highly modded race type engines, not so much on stockers. It may seem to "run good" but they dont have as much low to mid range power as with the webbing in due to the crankcase pumping loss.
It surely 110% has NOTHING to do what so ever with rod bearing failure.
the webbing is all about packing the case and controlling the velocity up thru the transfer ports, yamaha evidently felt the need to use it in the srx/viper engines to take control of packing the case. It was surely needed for the srx600 engine as the piston is very small for the case/port design, seen lots of differances when modding that engine.
engines with the webbing cut out will increase case volume, but if your not needing that case volume increase, would actually lose pumping effiency, not the other way around.
opended up cases work well with highly modded race type engines, not so much on stockers. It may seem to "run good" but they dont have as much low to mid range power as with the webbing in due to the crankcase pumping loss.
It surely 110% has NOTHING to do what so ever with rod bearing failure.
Great info mrviper. I would venture out and say maybe half of bottom end failures are caused by improper storage. It doesnt take long during humid spring/summer days for corrosion to start if the engine wasnt fogged. You might not realize it right away but maybe a few seasons later.
YAMMIEGOD3:16
Active member
SEEN WAY MORE SKIDOO,s TAKE LOWER ENDS OUT THAN YAMAHA,S. MACHZ WERE NOTEd FOR IT, SO WERE REVS, ALSO HEARD EVEN THESE,S XPs / tnt,s are blowing up. AND YOUR RIGHT, FOGGING VERY IMPORTANT. 3:16 (yammie tony)
jabber800
New member
I have found most trail ported engines to run better with the webbing left in! A full mod race engine running at 10000 rpm's + needs to flow a lot more air hence the removable of the webbing and extensive transfer port runner mods! also the transfer angles must also be re directed with the higher rpm's
Trail porting = minor work
Race porting = extensive work and money!
A lot of time involved to race port an SRX engine.
JMO
Trail porting = minor work
Race porting = extensive work and money!
A lot of time involved to race port an SRX engine.
JMO