How To Make A Moriwaki GP80 Go Faster

We Took The Moriwaki 80's And Made Them Go Quicker - Much Quicker

The MW80 dynoed at 20bhp - we got it to 25bhp with just a little bit of work. They also weigh in at 85kg, it's easy to shed 5kg off the bike but might be easier to get rid of more from the rider.........

Chassis Mods

The rear sub frame under the seat can be removed and replaced by much lighter supports - saving about 3.5kgs of wieght

The front forks can be made a little stiffer with less dive by putting 6 x 10 cent pieces under each of the spring caps and about 15ml more SAE 20/50 oil into each fork leg

A front fork brace can be added if required

A spacer of about 1.5mm inserted into the rear shock increases stiffness, but it also increases the rebound rate too, the real answer is to replace the shock totally

About 25 small brackets can be removed from the frame saving about 0.25kg. you can also bin the tank hinge mechanism and catch, saving another 0.5kg

All of the standard plastics can be replaced with fibreglass saving a further 2.00kg

Replace the front brake hose with a braided line

Replace Dunlop TT900's with something sticky!

Engine Modifications

Bin the round slide carburettor and replace it with a Keihin flat slide - Add 1.0hp

Port the barrel gently - Add 1.5hp

Use V Force Reeds and block - Add 1.25hp

Make sure that the compression ratio is 12:1

Use AVGAS RF100 - Add 1.0hp

Cleaning the inside of the expansion chamber and repacking the muffler seems to improve performance

Other Possible Mods

Use a 410 chain and turn down all of the sprockets to suit - this will reduce drive train losses

Replace the front disc with a bigger one and remount the caliper - removes brake fade

Put on a Vortex electronic ignition

If want to change the geometry you can change the headstock and triple clamps, but we never saw the need

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