back Axle

[mr Dee]

mr Dee wrote:
Hi i have a GL1100 trike with Sierra axle with disc brakes which are no good so changing back to drums which means buying secondhand Sierra axle on my axle the gear on the diff is 3.64 would i be better changing the diff to a different racio it does about 55 mph at 4000 rpm as anyone any thoughts on this many thanks Viv

[Kawazuki]

Have to ask - why are the disc's so bad as they are so superior to drums (unless its a series one landrover!) Did you change the master cylinder to match the disc calipers?

If a higher ratio diff is available then something 3:1 or taller would help providing the engine has the ponies to pull it!

[Deep Diver]

Does your gl1100 have the linked front and rear brake. If so blank off the feed to the front and have both front discs on the same circuit.
Lep has this on his gl1500 and it works ok

[mr Dee]

they are scorpio dices a calipers with a land rover master cylinder just seems very hard no progressive slowing feels like its not going to stop front brake is brilliant both dices are on front brake rear on foot pedal as for diff a 3.3 that's is what i should be looking for if i can find one mostly on ebay are 3.6. or 3.9 rear wheels are 18" with 225 x 40 tyres

[Deep Diver]

You may need a smaller diameter master cylinder. Also the length of the pedal makes a difference.

[Kawazuki]

Agreed a Landie cylinder is 0.75" but for disc calipers something with a 0.625" bore would likely work better - longer pedal but better pressure to the caliper pistons. Pedal ratio should be around 7:1
Can't help with the diff but I guess a 3.33 won't make a huge difference over the 3.6 - remember the car would have had an 0verdrive 5th gear so the lower diff ratio balanced out but guessing the bike engine will be 1:1 hence higher revs against mph!

[mr Dee]

thanks guys will look around for a smaller cylinder again thanks for the input Viv