| Author | Message | ||
     M1combat |
I'm wondering how long the XB engines tend to last at that level of tune. Do a lot of them end in smoke or are they generally pretty reliable? I'm mostly just asking about the engine itself as opposed to electronics etc... I've heard they're pretty reliable but I'd like to get the answer straight from the horses mouth. Thanks in advance. | ||
| Hurricaneleah |
M1 combat, You talking a true pro thunder XB? or an ASRA thunderbike? A true pro thunder xb is pretty rare these days (3.6" crank) and wiseco no longer makes pistons. Thunder bike the guys are running two configs, either 1170cc (xb9 stroke, big bore) or 1426cc (xB12 stroke, big bore). To achieve the hp level, the 1426 engine is very mild.....11:1 flat tops, stock cams, stock heads, etc, etc. The 2008 crank is a huge improvement in reliability and is pretty much bulletproof. The big risk with the big bore stuff is pulling the studs out of the cases....was worse on the tube frame motors it seems though. Personally, I prefer the long stroke 1426 over the 1170. I think you are asking for trouble anytime you rev an 1170 over 7500...A 1426 that sees a max of 7K seems to live in thunderbike tune more or less indefinitely. The true pro thunder bikes are in quite a bit higher state of tune (140hp), and as with any race motor, reliability suffers the shorter your fuse is. Thats pretty much the reason the XBRR came into existence....a much better platform to make big hp reliably. |
