If you have several bikes that shift "one down, three up," for safety reasons it would be good to have the option of the reversed cam plate for the rear-set shift lever, so down-shifting in an emergency can be done without having to think about it.
I have seen pictures of the aftermarket linkage to do this, and all look crude and "tacky."
For what this five-speed gear conversion will cost, It can't be that complicated to engineer a reversed shifter camplate for it. A conventional one has to be made, anyway.
Thank you for your comments Jon, much appreciated.
Irish. What about going from right to left change as well! There are a number of well made linkages on the market, or you can simple build your own to change it to one up. I'm trying to keep the costs down, building in a reverse pattern change is not just as simple as you might think and certainly for the time being one down four up is the way it shall be sold.
What it's like. Not the best video. Although its just short shifting into 3rd 4th and 5th, if you keep power on through all the gears the excellent ratios put you right on the power and rocket you forward. 4th to 5th is closer than the old 3rd to 4th, I wondered about that, but its perfect, if 4th is not low enough just below it is 3rd. The beautifully made cluster:
Hells bells there is not much mest between those slots. Considering the problems with the early A 65 boxes requiring strengthening to prevent the slots separating I hope they got their metallurgy spot on.
In answer to Anne's question. Sorry I missed your post. I'm fairly sure that an adaptor could be made to suite the Newby clutch, it would be a matter of talking to Newby, as this would possibly require new clutch centre, although I'm not to failure with the Newby clutch.
To answer trevor's question. There are a number of differences between the original selector plate and the 5 speed one. a) thickness b) heat treated c) the dogs are back cut, therefore the gears keep themselves engaged, unlike the original which relied on the selectors and selector plate to keep the gears engaged.
No, it's constant mesh, the gears are always in mesh and slide to engage dogs to connect or disconnect them, determining which gears drive the output. On this cluster those engagement dogs are robust and dovetailed so when they are engaged they tend to hold themselves engaged.
I'll take names of those interested now. The earlier I have enough names to run a batch the earlier I can get a production slot with PES, who are always very busy. Its would probably be towards the end of the year before they would be ready, but I'd have a better Idea once I have some interest and can make a commitment.
I can send anyone wanting more information on the cluster if they email me on firstname.lastname@example.org.
Your name goes to the top of the list. Yes you can swap the clusters out with the engine in the frame. Look forward to seeing how the clutch centre works on the Newby clutch. I know the Hayward clutch system uses the standard BSA centre, so that would just be a straight swap.
40th anniversary this year and a Rick Strange memorial. Could not think of a better reason to go. So the A65 I have been seeing there in the same frame you are using is not you ? Did you do this a coupe of times or are there other great minds out there ?
They are advertising an A65 gearbox and show an image of it in their advert, it`s a cassette type box and had me interested enough to give them a ring. Turns out it`s a 5 speed unit that uses a selector drum instead of the old style selector cam plate design with it`s inherent weaknesses. Apparently they have some prototypes out there being tested, interesting stuff they do if you take some time looking through their website.
I have the std primary with 21 front and 36 rear sprockets for final drive. So the gearing is very tall. The thing probably sounds a lot slower than it actually is. I think this illustrates just how nice these ratios are. Definitely made my BSA much more effective.
Simply put it was ALWAYS weak because of the design, there wasn`t much meat on it in places and hardening `may` mean it`ll be embrittled too and more prone to stress fractures. I had both a Lightning and a MkIV Spitfire, 66 model with twin GP carbs. The Spitfire broke it`s cam plate but I was pretty hard on it back then to be honest, it didn`t get an easy life.
I could not find any reference to a five speed cluster for the A65 on the Nova site. I would be really interested in how they fit a drum in place of the camplate. Even if the drum were offset from the fork guide rod it could only be about 1/2" diameter which would make for extremely steep and narrow tracks. Then the selection mechanism would have to completely change. The stock camplate was too soft which wore the points of the tracks and they had to add the stiffener plate on the backside to keep the tracks from spreading. They could have fixed that by making the camplate thicker and making the tracks blind if they had the tooling.