Drive chain versus drive belt?

**Taz** · 27th August 2009, 08:12

Don't notice any adverse effects on my Guzzi but then it doesn't rev very hard and it doesn't go very fast and it doesn't handle very well but by god it's a sensual ride. Every one should ride an old guzzi once in their life.

**Big Dave** · 27th August 2009, 08:32

Originally Posted by Anthrax

Don't notice any adverse effects on my Guzzi but then it doesn't rev very hard and it doesn't go very fast and it doesn't handle very well but by god it's a sensual ride. Every one should ride an old guzzi once in their life.

For a perspective on how nice their current bike is?

**red675** · 27th August 2009, 16:16

belts are mechanically more efficient (about 1% versus 2% in mechanical losses), unfortunately unenclosed belts frequently suffer early failure due to stones getting between the belt and pulley ...

when this happens it's off to the bike shop for a very expensive belt replacement and usually a long wait

**popelli** · 27th August 2009, 17:08

Originally Posted by Big Dave

I prefer properly designed belts.
I'd never have a chain again given a choice.

are you saving that harley has not designed the belts properly ??

**Big Dave** · 27th August 2009, 17:27

Originally Posted by popelli

are you saving that harley has not designed the belts properly ??

Nah - meant properly designed for intended purpose.

Mine has proved well designed for a gravel road. A Springer isn't - but it's a hornbag. Horses - courses.

**Pixie** · 28th August 2009, 11:48

Originally Posted by Big Dave

I played basketball with a bloke the owned one. He never missed a game - but they had a reputation for exploding - was it warranted?

You're confusing the TX 750 Twin with the XS 750 triple.

The twins had head gasket problems

**Big Dave** · 28th August 2009, 11:56

Originally Posted by Pixie

You're confusing the TX 750 Twin with the XS 750 triple.

The twins had head gasket problems

ah - temporary acronymic dyslexia

**Pixie** · 28th August 2009, 12:08

Originally Posted by Big Dave

I've owned and tested numerous shaft drive vehicles since the 70's.
2 x XS1100, GS850G - and dozens of test bikes.
Never experienced any torque steer with any of them. None. Nada. Nil.
Personally I think on the reports with the Guzzis it's the flywheel.

There is a lot of confusion about the various effects shaft drive has on a bike's dynamics.

First: the twisting to one side that BMW twins,horizontal triples and fours,Guzzis ,Honda ST 1300 etc. can potentially exhibit,is due to a fore and aft crankshaft.It is not due to the bike having a shaft drive.GS 850s XS 1100s BMW K1300 etc. have transverse cranks and do not rock to one side when the throttle is blipped.
In fact,you could design a fore and aft crank engine with a chain or belt drive and it would still twist to one side.

Second: the shaft causes the rear of the bike to rise.This is said to be caused by the pinion and therefore the swing arm that carries the shaft,rotating around the crown gear and forcing the swingarm pivot to rise.Thus causing the whole bike to rise.This is true.However a chain or belt drive exhibits these same forces but they are offset either partially or completely by an opposing force created by the offset force path along the upper run of chain or belt.

**Big Dave** · 28th August 2009, 12:16

Originally Posted by Pixie

There is a lot of confusion about the various effects shaft drive has on a bike's dynamics.

First: the twisting to one side that BMW twins,horizontal triples and fours,Guzzis ,Honda ST 1300 etc. can potentially exhibit,is due to a fore and aft crankshaft.It is not due to the bike having a shaft drive.GS 850s XS 1100s BMW K1300 etc. have transverse cranks and do not rock to one side when the throttle is blipped.
In fact,you could design a fore and aft crank engine with a chain or belt drive and it would still twist to one side.

Second: the shaft causes the rear of the bike to rise.This is said to be caused by the pinion and therefore the swing arm that carries the shaft,rotating around the crown gear and forcing the swingarm pivot to rise.Thus causing the whole bike to rise.This is true.However a chain or belt drive exhibits these same forces but they are offset either partially or completely by an opposing force created by the offset force path along the upper run of chain or belt.

Blipping the throttle when stationery on the Guzzis and BMWs is part of the pleasure. Whey-hey the goeses.

I agree with what you have said. But I am still yet to notice (or fail to recall) any gyroscopic or other effect in the course of normal forward progress.

This could be attributable to my larger than average mass.

**Edbear** · 28th August 2009, 12:37

The faster I go forward the more effects I get...

Must be something to do with my mass...

**Big Dave** · 28th August 2009, 12:40

Originally Posted by Edbear

The faster I go forward the more effects I get...

Must be something to do with my mass...

There is a difference between gyroscopic effect and spinning out. :-P

**BMWST?** · 28th August 2009, 12:49

Originally Posted by Big Dave

Blipping the throttle when stationery on the Guzzis and BMWs is part of the pleasure. Whey-hey the goeses.

I agree with what you have said. But I am still yet to notice (or fail to recall) any gyroscopic or other effect in the course of normal forward progress.

This could be attributable to my larger than average mass.

the guy was referring to the rise and fall of teh shafties...My xs750 e did this more than my k100rs and current BMWR100GS

**Big Dave** · 28th August 2009, 13:32

Originally Posted by BMWST?

the guy was referring to the rise and fall of teh shafties...My xs750 e did this more than my k100rs and current BMWR100GS

Yeah - I got it.

**caseye** · 28th August 2009, 22:54

Originally Posted by Big Dave

I've owned and tested numerous shaft drive vehicles since the 70's.
2 x XS1100, GS850G - and dozens of test bikes.
Never experienced any torque steer with any of them. None. Nada. Nil.
Personally I think on the reports with the Guzzis it's the flywheel.

Dave it wasn't torque steering, ie: making the bike go left or right. it simply made the back of the bike rise!
My GS850 G also a shaft drive did not do this, somewhere between the early 70's and the early 80's they got rid of this pesky little problem.Wasn't really that bad, once you got used to it, but boy did it scare the pillions, the girls grabbed on much harder when that happened.