Forum

[devon john]

as i have the spair bullet gearbox in bits i have cleaned up a few of the gear change selector parts ,, i have polished them

i was going to polish all the faces of the foot control plates as i am waiting for parts ,,, wasting my time or posable advantage ????

john

[Leon Novello]

Some parts are deliberately made rough to work properly. Years ago Rolls Royce were using Holden`s GMC Hydramatic gearboxes; striving for perfection with their machinery, they machined a rough (I think it was a shaft) smooth, the gearbox didn`t work until they fitted a standard rough shaft. Maybe it is an urban myth, but it was probably over 50-years ago that I read about it..

[Presto]

Polishing gearbox parts? Can’t see it creating a problem. Equally I can’t see it making a scrap of difference in a gearbox as ‘robust’ as the Enfield ‘box. In fact can’t see polishing anything inside a Bullet engine making any noticeable difference to anything. If it was a Rolls Royce that might be different - but a Bullet isn't a Rolls Royce, perhaps it's about as far from a Rolls Royce as engineering will allow!

[Trev]

Interesting, never hear of this and I've rebuilt a few bike (and other) gearboxes over the years. I would say you're wasting your time but intrigued to hear from anyone with first hand knowledge of anything to be gained by it.

[Cafeman]

John, some improvements can be made by easing with a file or some emery cloth the edges of machined areas on the shafts and dogs on the gears, "if" there are any sharp edges that exist. Simply placing various gears/clusters on the shafts and sliding them within the area on the shaft where they operate you can determine if a little easing on the shafts is needed. On my gearbox rebuild (w/close ratio gear set) a couple of the cogs did not slide on the shafts smoothly, so I carefully and mildly eased those edges, just ever so slightly. Made a difference sliding the gear clusters by hand, as well as shifting while riding. As to polishing things? It may help, it might not. I say grab a beer or two and have at it!

[Gwilly]

Agree with Cafeman, after all we fettle the clutch plates and splines by easing out highspots and wear notches and this always pays dividends in smoother engagement..

Plus its not often we get the gearbox apart so take the opportunity to carefully examine the teeth and dogs for chips, cracks and wear requiring replacement parts..

Mass produced indian engineering with parts thrown into a bin awaiting assembly, guess some bits will fit better than others...

Polish and deburr the inner and outer ratchet assemblies, also the gosa, (indent plunger) still has a chiseled edge that fits squarely into the gear operator,(bell crank)..

All that time and attention you'll have the smoothest gear change in Devon..

[vince]

Harley Davidson filled their racing gearboxes with a mixture of oil and grinding paste and turn it over for a few hours with an electric motor to smooth all the surfaces, it was then stripped cleaned and new bearings fitted. And Triumph desert sled specialist polished and modified their gearboxes with breather pipes etc. Anything to reduce oil drag, maybe there is some merit in it! Vince

[Presto]

I think my view is based on the idea that the remainder of the engine and transmission components of a Bullet are not of a type to allow you to experience any great benefit from the marginal improvements de-burring and polishing of a few discrete components may make. On the other hand, as we know, ‘blue-printing’ an entire engine can deliver monumental improvements. Go for it John - and let us know the results.

[devon john]

thanks for the replies ,, it was how pore the gear selector face was and as i had time i thought it could do with a little file and then polish ,, i then filed up the indents and polished the surfaces of the selector mechanism ,,
i am going to run it on fully synthetic gear oil ,,, i am in no hurry to change it yet but will after a trip to France in May

[bigpete]

I found on my 350 bullet not to have the indent plunger set too tight as this does make the gear change stiff. cheers Pete