Just getting back into bucket racing.
Had the MB100 dynotuned in prepartion for the Battle of the Buckets at Ruapuna on 15 Oct 11. Results (shown below) were mixed.
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Positives from the session on the dyno were:
1. The bike is no longer in grave danger of seizing because it was running way, way, too lean.
2. I actually know where its making power and can now ride it accordingly.
Negatives:
1. Bike is making less power than expected and is quite peaky. Peak power is also being made quite low at around 9200rpm. Exhaust seems to be the culprit on this.
2. Carb seems to be too large for the bike. Diagnosed from:
No power increase with a jetting increase.
Jetting also can't be increased as carb won't flow enough air. Raising the needle to flow more air (to allow bigger jet) just causes bogging issues.
Unable to reduce the jetting size without compromising the fuel/air ratio and placing the engine at risk
What I don't have is an objective point of view of what can reasonably be expected from this motor and where I should start to try and improve it. I've heard figures of upto 30hp being bandied around, but would be happy with a little more than what I'm getting over a much broader rev range.
Bike is running a Mikuni carb that's been machined out to 27mm and what looks like a home made exhaust system with a can of unknown origin.
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