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Rear sprocket damper

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Good evening people

 

I was wondering, does anyone know of a way to substitute the DR's rear hub assembly with one that has the damping pads nearly all motorcycles have. Those mechanical shocks are a pain.

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The trouble with using another make hub is finding the spokes to go with your rim, apart from sprocket alignment, it may be necessary to have new spacers made.

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The trouble with using another make hub is finding the spokes to go with your rim, apart from sprocket alignment, it may be necessary to have new spacers made.

I think the general idea is to use a KTM wheel/hub that is correctly sized for the DRZ,..

http://www.thumpertalk.com/topic/408849-ktm-wheel-fitment-the-how-to-%E2%80%9Cbig-pics%E2%80%9D/

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Thank you so much for this great information, I'll look into it carefully. I really don't know what some manufacturers are thinking when they make bikes without this damping, which obviously reduces lifespan and makes for hard shifting and all sorts of other problems (bearings coming loose in the hubs for example).

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AAAh no.  Hard to say life span is reduced when DRZ last as long as they do.  Look at all the motorcycles new and old that do not and never had damper hubs.  Perhaps damper hubs are over rated.

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I had a Honda XR 250 that was also undamped. People were complaining all over the place about shifting problems, bearings coming loose in the hub. One common fix was to have the hub machined to fit a pair of larger bearings, mimicking the damped setup in a way. First thing I did was to get a damped hub, thankfully from an upgraded honda model that had exactly the same geometry, so it was plug and play. Maybe the DR's are sturdier and can take the beating, still I can't see how damping would be a bad thing. I'm looking around for KTM hubs/wheels, but only found one, undamped. Not surprising, as these machines are niche over here. However i found reference to the Honda NX 400, it seems to be a perfect fit, although maybe not as strong as the DR's. Since I'm not contemplating any offroad riding, this just might do it.

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IMO, for serious off-road use, I am not sure that it is a huge improvement.  I ride 99% pavement on an SM and run a rear CBR rear wheel with the cush hub and it makes the shifting smoother along with a smoother overall ride.  I have run over 35K miles with the cush rear hub and I'm sure that my chain and sprocket life has been improved with the cush drive.

 

I considered the Cush sprocket before going with a different rear wheel, the cush sprocket looks like a reasonable way to add some cushion to the drive system, but if you change gearing or ride a lot of miles, replacements or optional sizes will get expensive.   It would be very good to hear from someone using the latest generation of the cush sprocket.

 

There must be a reason why in Japan, they run a cush hub on the SM models...  (Suzuki in the US was probably trying to keep some cost out, or maybe the profits up... and opted to not have the cush hubs)

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Re. kush sprockets, there is some discussion on advrider.com and husaberg.org. I haven't tried but I've gathered enough second-hand evidence to convince myself to try one :)

 

Tangentially related - certain KTMs and Husabergs have occasional countershaft spline wear issues; The theory is that an un-damped drivetrain plus pavement use coupled with non-knobby tires will shock the driveshaft splines enough to wear them out. The DR-Z doesn't have this issue, but it's interesting, and illustrative of the mechanics involved. In a way, aggressive knobbies with tall knobs are a form of damping - the knobs flex and wiggle. It can certainly be felt in turns, and I'm sure it damps drivetrain shock somewhat.

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Tangentially related - certain KTMs and Husabergs have occasional countershaft spline wear issues; The theory is that an un-damped drivetrain plus pavement use coupled with non-knobby tires will shock the driveshaft splines enough to wear them out. The DR-Z doesn't have this issue, but it's interesting, and illustrative of the mechanics involved. In a way, aggressive knobbies with tall knobs are a form of damping - the knobs flex and wiggle. It can certainly be felt in turns, and I'm sure it damps drivetrain shock somewhat.

 

:thumbsup: Agreed...

 

Certainly the sticky sport bike tires run on pavement were probably not taken into consideration when some of these "dirt" bikes were initially being developed.  Probably the reason why Japan added the cush to the DRZ SM model there.  The power of the KTM's and the Husabergs with the sport bike tires would exaggerate any weakness in the drive systems.  Knobbies would provide a level of dampening and they do not have the stick of the tires run on a SM model.  

 

Even when just riding through town at 30 - 35mph, the cush also helps smooth out the thumper aspect when ridden on pavement. 

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IMO, for serious off-road use, I am not sure that it is a huge improvement.  I ride 99% pavement on an SM and run a rear CBR rear wheel with the cush hub and it makes the shifting smoother along with a smoother overall ride.  I have run over 35K miles with the cush rear hub and I'm sure that my chain and sprocket life has been improved with the cush drive.

 

I considered the Cush sprocket before going with a different rear wheel, the cush sprocket looks like a reasonable way to add some cushion to the drive system, but if you change gearing or ride a lot of miles, replacements or optional sizes will get expensive.   It would be very good to hear from someone using the latest generation of the cush sprocket.

 

There must be a reason why in Japan, they run a cush hub on the SM models...  (Suzuki in the US was probably trying to keep some cost out, or maybe the profits up... and opted to not have the cush hubs)

What CBR wheel would that be exactly, is it spoked ? Otherwise wouldn't it look strange ?

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Take the shock out of the drivetrain and converts it to heat in the cush rubbers, easier on everything in the gearbox, I have a CBR250 rim for my S with a cush drive, cheers

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What CBR wheel would that be exactly, is it spoked ? Otherwise wouldn't it look strange ?

 

I took the wire wheels off my SM and went to alloys... Cush drive, no tubes and no no spokes to tighten.

 

Do a search for "CBR F2 wheels" and you should find plenty about them.  Or do a search on "Hooligan mod" and you will see more alloy wheel information.  Many have used sport bike wheels on "S" or "E" models to fit 17" SM set-ups...  

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What do the springs on the back of the clutch basket do?

 

Do they only act whilst the clutch is engaging or are they helping all the time (similar to the dual mass flywheels used in modern diesel engines).

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Is there a disadvantage to using the Kush Sprocket for light duty dirt riding?  I can see why a racer wouldn't want it but for a dual sported DRZ on dirt roads and trails I think it could be a good thing.  I have the Rekluse auto clutch and that does add some snap to the driveline with each shift.

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