Flatty ratchet top

[tomo256]

Hi Guys.
I am looking for some advice please. I had an issue with riding my big flatty recently with has normal hand change / foot clutch. I had to take evasive action and instinctively grabbed for the hand clutch, which obviously wasn't there. I ended up mounting the pavement (sidewalk) but it ended well with no damage. I am seriously considering fitting a ratchet top to the gearbox and converting it to hand clutch and foot change, simply because I just want to ride the bike safely and not have to seriously think about every gear change.

Flayyt box.jpg (23.18 KiB) Viewed 662 times

Can anyone please tell me if a ratchet top, (which I have already) will fit in the space below the gearbox, and the ratchet top dust cover will not foul on the oil tank. I have included a photo of the set up as it is now. The gearbox top that is on the box now is a reproduction part. I am aware of the issue of shimming the selector forks and have the shifter fork position gauge and have done it previously. I just didn't want to pull it all apart for it not to fit. Any advice as always greatly appreciated.

Martin

[RooDog]

The architecture is the same for most model Big Twins from about 1941-64. The only caveat I would have to offer you is the transmission rear drive sprocket size. Anything much larger than 24 T may run the chain into the shifting ratchet, especially if the chain gets loose, or worn. You need to maintain operating clearance. With a hand shifter, this is not an issue and as big as 26T will work in that case. Weather I am right or wrong about the appropriate tooth counts, be sure you do have clearance with a safety margin with the rear sprocket & chain.
....RooDog....

[RUBONE]

No issues with switching the tops. If you are not planning to use a mousetrap then some changes to the clutch pack will be necessary to allow reasonable lever pull. If you are then any of the parts you have should work. Inner primary covers differ slightly but not an issue on your bike.

[tomo256]

Thanks for the replies, I do intend to use a mousetrap, I know I have one kicking about here somewhere.

Martin

[RUBONE]

Thanks for the replies, I do intend to use a mousetrap, I know I have one kicking about here somewhere.

Martin

That should make it all quite simple.