So I have tried most of the suggestions here to firm up the front brake lever but still too much initial movement. Bled them to death and other methods but still not satisfactory in stopping a bike this fast.
On taking the calipers off and pulling the lever I noticed on releasing the lever that the pistons retract a fair bit thus needing more lever to get them on the disc again.
I know the seals and the seal recess are designed to make the pistons retract slightly on releasing the lever but in this instance it seems way too much thus leading to a long lever.
Anyone had this apparent issue??
I have noticed the very same thing. Threw in some new seals but it really is much the same with only a slight improvement. I have noticed on my Blackbird which is still a 20 year old bike that the seals are about half the cross section so the pull back is significantly reduced.
Yesterday I rode my RF then Blackbird to their MOT tests,my R has very little lever travel,floating discs(on cbr wheels)HH pads,braided lines,stainless pistons and slide pins along with dot 5.1 fluid.
These brakes are good BUT on setting off with the bird(having not ridden it in over 4 years)I did myself a mischief on the tank with the first pull of the brake lever.
The two are not in the same league.
As good as they are the VF brakes are only adequate for a bike this weight.
The slide pins are key to getting the most out of them,the caliper has to float freely or extra lever travel is generated.
Genuine pin boots are essential imho as aftermarket items I have tried don’t have the correct tolerances.
Once assembled I pump the pistons out until the pads almost touch then lever back until they just fit over the disc.
This method reduces the pull back on the seal as the piston travel under pressure is minimal
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Yeah I have noticed that some boot pin rubbers are such a tight fit that the caliper pin will not move. I reamed mine out with a Dremel and they now slide freely. Maybe I’m overthinking how good 1984 brakes should be.
A comment about the rear brake pedal. I would like mine to be higher but you can only move it a couple of splines before the lever pinch bolt comes up against the footpeg bracket. I can’t see any other way of getting it bit higher besides grinding some of the footpeg metal away or countersinking the bolt head.