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[lilcoot]

Is there any legitimate reason to replace belt drive with chain drive at the rear wheel on a Harley?

Saw an '09 non-CVO Road Glide today with a chain rear wheel drive.  The owner said he had it done after extensive drivetrain mods, including an S&S 124" motor.  He said he had changed to chain drive after breaking the belt not long after doing the performance upgrades.  This seemed odd because I don't recall reading anything here about needing to convert to chain drive after performance mods, but he insisted it's necessary, and not that unusual.

My BS meter was going off, but I had no real information on the subject, besides the shear number of belt drives vs chain drives.  My impression about chain drives is that they are noisier, messier, require more upkeep, and are no stronger than belts.  Having seen the damage a broken chain can do to the casings of quads and dirt bikes, I shudder to think of the damage to a Harley's primary.  The only advantage I can think of is that they are easier to fix, and maybe are less bulky.

Was my BS meter right, or are there more more chain drives out there than I'm aware of?

[hd-dude]

Your bs meter was right. Chains are stronger, that is a fact but its all in how the bike is ridden. I have replaced snapped belts on bikes with stock 88" and 96"  motors. Guys that like to do burn outs wheelies and hole shots are the ones that need a chain dive. They will also be needing transmission and primary parts in short order too

a few years back i had a RUB that came in with a fried clutch. He fried it being stupid with the bike. We replaced the clutch for him and when he picked up the bike he was very concerned about the clutch not hooking up enough. I told him it would be fine and when he pulled out of the parking lot he proceeded to whip the RPM's up and dump the clutch, when the belt came flying out of the back of the bike I couldn't help but walk out and tell him that the clutch hooked up.....

[grc]

Only thing better than a modern belt drive on a street bike would be a shaft drive.  The only "advantage" of a chain drive is the relative ease of roadside repairs assuming you carry spare links and master links.  Hd-dude hit exactly on the reason some folks seem to feel a need to convert to chains.  They abuse the heck out of the bikes, and at least for the short term the chains will hold up a little longer.

I definitely don't miss the bad old days of cleaning and lubing chains, and absolutely don't miss the failures where the chain either whipped off and got flung into the weeds on the side of the road, or much worse got wrapped around some hard parts and locked up the wheel or engine.

Jerry

[Spiderman]

I've never personally BROKEN a belt but I had the teeth shear off an 86 FXR that I hotrodded to a 100+hp. Of course it was the orginal belt and the incident I'm referring to took place in 94 so hell, the damn belt was 8 years old. Thing is, even when I'm doing good with a diet, I'm never far from 300lbs and I've had bikes with well in excess of 100hp and 110ftlbs an never broke a belt. To back up what Jim is saying though, I don't do hole shots. Never trusted how the rear tire was gonna hook up and have seen many a hole shot go south when the rear end went east or west. Anyway, chains I guess are the choice of racers for strength and service issues. Shaft drives are for little old men who never twist the throttle very much at any time and as such never notice that it takes all those gears and joints awhile to catch up with each other creating a hell of a lag between twisting the throttle and actual launch. - - -my 2 cents on that only, I'm sure there's members out there who just love a shaft.   

B B

[grc]

OK Brian, just how many shaft drive bikes have you actually owned over the years?  I've owned several, and I'll tell you there was only one real difference when I wacked the throttle.  On a chain or belt drive bike, the rear end tends to squat on acceleration.  My shaft drive bikes did the opposite, with the rear end rising slightly.  Once you get used to that difference, the shaft is great.  There is no additional "slop" or delay in putting the power to the ground; don't forget we aren't talking about the sloppy tolerances Harley uses on their stuff.

Btw, even though Harley doesn't install a shaft drive on their bikes it doesn't mean they don't give us the shaft as often as possible.

Jerry

[Rooster]

I've never personally BROKEN a belt but I had the teeth shear off an 86 FXR that I hotrodded to a 100+hp. Of course it was the orginal belt and the incident I'm referring to took place in 94 so hell, the damn belt was 8 years old. Thing is, even when I'm doing good with a diet, I'm never far from 300lbs and I've had bikes with well in excess of 100hp and 110ftlbs an never broke a belt. To back up what Jim is saying though, I don't do hole shots. Never trusted how the rear tire was gonna hook up and have seen many a hole shot go south when the rear end went east or west. Anyway, chains I guess are the choice of racers for strength and service issues. Shaft drives are for little old men who never twist the throttle very much at any time and as such never notice that it takes all those gears and joints awhile to catch up with each other creating a hell of a lag between twisting the throttle and actual launch. - - -my 2 cents on that only, I'm sure there's members out there who just love a shaft.   
B B

One coffee spew for this morning. Thanks B

[North Georgia Hawg]

OK Brian, just how many shaft drive bikes have you actually owned over the years?  I've owned several, and I'll tell you there was only one real difference when I wacked the throttle.  On a chain or belt drive bike, the rear end tends to squat on acceleration.  My shaft drive bikes did the opposite, with the rear end rising slightly.  Once you get used to that difference, the shaft is great.  There is no additional "slop" or delay in putting the power to the ground; don't forget we aren't talking about the sloppy tolerances Harley uses on their stuff.

Btw, even though Harley doesn't install a shaft drive on their bikes it doesn't mean they don't give us the shaft as often as possible.

Jerry

I had a 1985 Kawasaki ZL900 Eliminator with a shaft drive. And yes, due to the shaft rotating force, the rear end did lift noticeably when accelerating hard. It was kind of fun, really!q

There was no slop in that shaft drive at all... but due to the mass of the shaft and of the gears at the rear end, shaft drives are slightly less efficient at transferring power to the rear wheel than a chain or a belt drive.

My experience with that bike was that the shaft drive was very smooth and quiet, as well as super-reliable... it is a fully-enclosed system. I only had to change the fluid occasionally, and I never had to be concerned with breaking a chain nor a belt. I like shaft drives for that reason.

Ken

[ultrafxr]

Had a Suzuki GS in the 80s that had shaft drive. No problem at all. No maintenance except fluid and removing rear wheel was a breeze.

[05Train]

Yup, I miss the shaft drive on my GS/A.  I could have the rear wheel off in about the same time it takes to remove the bags from my CVO. 


Sent from my iPad, probably while I'm pooping.

[Fired00d]

My first bike was '79 XS1100 Yamaha w/shaft drive that I put a 4-n-1 Kerker Header and "Drag" handlebars on. Didn't know any better (at the time I was young, dumb, and full of..) and I rode that bike like I stole it. I did burnouts and wheelies like it was nobody's business and never had any trouble out of it. As was mentioned earlier it was weird having the rear end rise on hard accelerations vs. squatting as chain/belt drives do.

 
Ride Safe,
Fired00d
 

[moscooter]

 
"My shaft drive bikes did the opposite, with the rear end rising slightly. "

Jerry,  exactly correct.   I used to ride a buddys 750 Suzuki with the shaft drive.   The pinion gear makes an attempt to "climb up" the ring gear ands thus raises the rear of the suspension.  When you would let off the throttle,  the rear would settle back down.............kinda strange feeling.

[MadCVORG]

I started out on an '82 Yamaha Maxim 650 shaft. Although the rear end climbed a bit on throttle, I got used to it. Had some concern on the Harley belts, but I never had a problem with mine.....and that's 18 years on the original.

[timo482]

ya, well where the problem is is in corners

if you are in a corner a bit too hard with a shaft drive - and freak out and get off the throttle the rear drops, firmly planting whatever bit of metal you heard that made you freak out solidly into the surface of the road sending you directly into the ditch, tree, guardrail, etc at the outside of the turn.

so if you have your wits about you you have to get on the throttle more and hope you run out of curve before the rear end quits rising... 

the rest of the time a shaft drive is quite nice

recently there have been issues ive read of some beaners with final drive problems - when a final goes out it makes a belt look positively perfect

but i never drive like that anymore, ride a ultra with a sidecar and avoid the whole thing........

to

[Fired00d]

ya, well where the problem is is in corners

if you are in a corner a bit too hard with a shaft drive - and freak out and get off the throttle the rear drops, firmly planting whatever bit of metal you heard that made you freak out solidly into the surface of the road sending you directly into the ditch, tree, guardrail, etc at the outside of the turn.

so if you have your wits about you you have to get on the throttle more and hope you run out of curve before the rear end quits rising... 

the rest of the time a shaft drive is quite nice

recently there have been issues ive read of some beaners with final drive problems - when a final goes out it makes a belt look positively perfect

but i never drive like that anymore, ride a ultra with a sidecar and avoid the whole thing........

to

Back in the day when I had the bike w/the shaft drive I was hanging off the side of the bike in the corners so there was no letting off the throttle. Now that I'm older (mature) and have bionic (replacement parts) I don't do that anymore.

 
Ride Safe,
Fired00d
 

[spada84]

My Moto Guzzi 2000 V11 Sport does not experience shaft jacking, but it has a complex swing arm arrangement.  My other 2 MGs do lift the rear, but not an issue once you are used to it. 

Belt is my overall preference, except when I'm putting on a new rear tire.

[grc]

I never really had an issue with cornering clearance with my shaft drive bikes, but of course this was back in the 80's before it became cool to lower bikes.  Like Fired00d, I knew how to actually ride a sporty bike back in the day and didn't just sit planted in one spot, so I never had concerns with grinding the hard parts whether I was on the throttle hard or easing off in the curves.  But the point is well taken; if folks don't know what they're doing and haven't practiced on their bike before going nuts, bad stuff can happen.  Sort of like when guys on Harley's drop the suspension to look cool and then plant solid parts in the asphalt while trying to make a curve.  People need to learn their limits and use basic sense, regardless of what they ride or drive.

Jerry

[Dan_Lockwood]

Does it matter which side the shaft drive is on?  If on one side versus the other, the shaft will turn in opposite rotation and the torque, or lift, would be reversed from side to side.

Or is my thinking all BS?

[moscooter]

 
I'm kinda thinkin' you do indeed have it wrong.  Which ever side the shaft is mounted on, the pinion gear would be pulling down on the teeth of the ring gear (thus "climbing up") in order to rotate the tire/wheel in a forward direction.

[The Mysterious Q!]

I have snapped two belts in 3 years and replaced a 3rd that had a stone imbedded in it. I don't do burnouts or wheelies. It's basically a 95" with a few performance mods. I just upgraded to the carbon fiber belt lets see how long this lasts. One thing I read on the install sheet is that for performance installations go tighter with the belt rather than the stock tension. I guess we will see.