Final Drive gear ratio's

[younger06]

What would be the main difference between 32/11 and 31/11 ??

I'm looking for a final drive and from what I can gather.....the Adventures have a 32/11 and the GS have a 31/11

My bike is an Adventure.......what effect would putting a FD from a GS have on the performance (if any) ??

 

[Tractors are go]

If you divide them it will give you % ratio then subtract first from second this will give you the difference between the two.

The gs will have a higher ratio (lower number) as it doesn't have as much mass to move off the line. So in theory a GS f/d would give you a higher top speed than a gsa, however aerodynamic drag and power output come more to the fore so in reality there is likely to be bugger all difference except top speed in intermediate gears. The bigger issue is extra clutch wear getting off line etc.

If, it was to replace a knackered one inexpensively fine, otherwise why bother ?

I am sure that other's will have totally different view's and opinions.

Sent from my GT-N7105 using Tapatalk

 

[Bendy toy]

32/11 = 2.909 31/11 = 2.818


2.909 / 2.818 = 0.9688. Near enough 3% difference.

It will affect the speedo reading and maybe the ABS so check if the ECU can be adjusted for the different ratio.

Some GSAs had a lower first gear. Mine doesn't so clutch can be hard work in very slow traffic. Ive no idea what final drive ratio I have.

 

[Greyscout]

It will throw up an ABS fault because the graduated spacings on the ABS ring will not match the ones on the front fwheel. So they will be passing the two sensors at different speeds which throws up a fault. If you can find a matching front ABS ring to go with your replacement FD, then you will solve the problem. You can't change the rear one as it is part of the crown wheel inside the FD.

 

[Bendy toy]

It will throw up an ABS fault because the graduated spacings on the ABS ring will not match the ones on the front fwheel. So they will be passing the two sensors at different speeds which throws up a fault. If you can find a matching front ABS ring to go with your replacement FD, then you will solve the problem. You can't change the rear one as it is part of the crown wheel inside the FD.

A good reason to contact Mikey or Steptoe when a final drive throws a wobbly. Trusting the average breaker to know what they are selling could cause problems.

 

[younger06]

A good reason to contact Mikey or Steptoe when a final drive throws a wobbly. Trusting the average breaker to know what they are selling could cause problems.

Right lads, thanks. It's not as straightforward as I thought (as is usually the case) so I think I will just get my own one rebuilt.

 

[DrFarkoff]

Fitting the 31/11 will raise the gearing and you will struggle even more when loaded and getting a hill start going

32/11 is 2.9 to 1 which is 2.9 revolutions of the propshaft to 1 revolution of the back wheel

31/11 is 2.8 to 1 which is 2.8 revolutions of the propshaft to 1 revolution of the back wheel

Better sticking with what you have Methinks

 

[Bendy toy]

Mike's and Steppers charges for rebuild are very reasonable.
Some years ago Patzx posted a thread showing how an FD is stripped. The state of his pinion nose bearing was indeed shocking and the drive had done (iirc) under 20K miles.
This makes a rebuild the more reliable option than a new used FD. Costs are similar.


Sent somehow.

 

[younger06]

Have found a new (old stock) FD in Germany....... the new type flange has been retro fitted and he is offering a 12 month warranty.
It has a scratch on the casing (why it was never sold) and I'm hoping to get it for €500 yoyos.

Sent from a OnePlusX

 

[younger06]

Motorworks charge £495stg for the used units (unknown mileage and only visually inspected)
6 month warranty......... I think.

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[comberjohn]

Sounds like a good buy, Keith.
When my main seal failed I was lucky enough to find an R9T FD from a breaker in Holland with 4k miles for £350. Paid for Monday, delivered Wednesday the same week!
Same ratio as the GS in case anyone needs to know.
Going by the manufacturing date stamps and condition, I would say the mileage was pretty accurate. Darker paint, but looks fine.
If you don't go for that one, would it be worth looking for the TC FD?
Supposed to be compatible, but with better internals.
Seals are still crap, though.

 

[younger06]

Sounds like a good buy, Keith.
When my main seal failed I was lucky enough to find an R9T FD from a breaker in Holland with 4k miles for £350. Paid for Monday, delivered Wednesday the same week!
Same ratio as the GS in case anyone needs to know.
Going by the manufacturing date stamps and condition, I would say the mileage was pretty accurate. Darker paint, but looks fine.
If you don't go for that one, would it be worth looking for the TC FD?
Supposed to be compatible, but with better internals.
Seals are still crap, though.

I have been led to believe (and I'm fairly sure it's correct) that the drive shaft on my pre 09/2007 will not mate up with a later model final drive.......the changed the drive shaft splines for the 2008 model. I had the opportunity to by a complete swing arm with FD from a Triple Black but it would not be compatible with my gearbox splines.

 

[comberjohn]

Pity. Must have been thinking of the version just before the TC.
Looks like that German unit might be the way to go. Mikey bought my old FD to refurbish and keep for a quick turnaround.
Might ease the pain a bit.

 

[younger06]

Pity. Must have been thinking of the version just before the TC.
Looks like that German unit might be the way to go. Mikey bought my old FD to refurbish and keep for a quick turnaround.
Might ease the pain a bit.

That's a great idea John, I will contact him about that.

 

[Mr Bean]

I have been led to believe (and I'm fairly sure it's correct) that the drive shaft on my pre 09/2007 will not mate up with a later model final drive.......the changed the drive shaft splines for the 2008 model. I had the opportunity to by a complete swing arm with FD from a Triple Black but it would not be compatible with my gearbox splines.

Not sure if relevant but I put a 2012 swing arm/drive shaft and FD (with breather) on my Feb 2007 RT and did another 20k miles on it before selling.

 

[younger06]

Not sure if relevant but I put a 2012 swing arm/drive shaft and FD (with breather) on my Feb 2007 RT and did another 20k miles on it before selling.

That is relevant........ thanks.

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[Bendy toy]

My understanding (always take care with that) is the Hexhead 1200 used the same basic components so they are interchangeable. But (for eg) up to 2008 FDs had a smaller pinion nose bearing 30 instead of 32mm. They were not as robust so there may be other changes on 2008 onwards to improve lubrication.
I also use at least 200ml in my FD one time it had 220. It's never overflowed.


Sent somehow.