Exhaust Gas Analyser

Yes, that is the benefit of the NTK unit, you can actually tune under real world conditions. I would imagine that drag racing would be almost all wide open throttle and the most difficult thing would be staying at or above peak torque when you release the clutch. You need a skinny girl who weighs 40kg as the pilot

 

Assuming the needle, emulsion tube and main jet are the only things that you would be messing with, it may be best to get one of those Keyster tuning kits that @kiffsta posted about recently and then play about. I think the on-board AFR monitor suits someone like me who will never see a dyno, because there are none, and has made so many changes to the bike that it is sure to run poorly. I will be able to just trundle along and take notice of where it is good and bad on the monitor, but if you only ride this bike at the drag strip then it sounds like an unnecessary expense.

 

• With a dyno you are just getting one reading for all four cylinders.

• Dyno costs are just going to accumulate while you change jets and return to try again.

• A GoPro would be the thing so you can just check your tacho vs AFR.

• The AFR is going to be a useful piece of kit if you are a bike nut who likes to tinker.

• The headers can be restored to whatever condition you want

• If you wait 399 years I will have my Yamaha together and I can let you know how it works out.

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Methanol will not achieve much unless you are running a gazillion to 1 compression ratio and you need it to stop detonation. "Ooops I forgot to fit needles and seats that can flow 200% more" Boom! There goes 4 pistons.

From the videos I have seen of small bikes at the drag strip, like the 250, they just bog down off the line. I would think that the rpm should never drop below 11000. I would use small tyres, light rider, low gearing and a clutch that can take a ton of abuse.

 

And maybe add some weight to the flywheel to get moving off the line better.

 

A heavier flywheel will give more inertia off the line and stop the revs from dropping too much.

 

The only one I've ever done was on a Honda Elsinor. We machined a piece of thick walled steel pipe to make a shrink fit over the outside of the magneto flywheel, heated and fitted, then machined the outside smooth/round. It slowed the engine from 'jumping' onto the pipe too quickly and made it more rideable. I didn't notice any difference with engine braking/slowing down. I cannot remember what the finished weight difference was (in was in 1977) but I think it would have been about 10mm thick, and about 40mm wide.

 

This was on a silver tanked 250. It also had forward mounted shocks and longer damper rods in the forks to give more suspension travel. Hmm, the stuff I used to do. Pity we didn't have any good cameras then.