drive train backlash

[Tfrank59]

I noticed a long time ago, soon after buying my bike, that there's a fair amount of backlash in my drive train, like when I let off the throttle and get back on it, and I'm wondering if that's something others have as well.  It's not like a clunk or slop I'm feeling but just maybe seems a little more than it should be.  I recently changed my rear tire and while in there inspected the dampers and all the splines and pinion cup, etc. and it all looks fine--good as it ever has in the 60k I've had the bike.  I have not removed or checked out the u-joint and based on what I've read on this forum about it I don't suspect it's a problem, though I can't say for sure.  Just want an opinion if the backlash thing is normal or not, in your view.

[hubcapsc]

New dampers are so tight it is hard to get them to go in... how did you
check yours? I wiggled mine behind the backing plate the other day
and called them good, no rubber dust to speak of... I've thought that
new dampers have made that "lash feeling" on my bike better in the past...

-Mike

[Jess from VA]

Mike beat me to it.

Some years ago, I put in a guy's (Shockbushing Gary RIP) custom made polyurethane dampers on both bikes, and it tightened both right up.  The OE rubber ones weren't really bad, just old (and I still have them, because I'm a pack rat).

My polyurethane ones wouldn't even fit in the slots, until I realized I had them upside down.  

I lost a Ujoint once, and got all kinds of grinding and thumping (making it home).  That's a different kind of driveline slop; and if a Ujoint starts going bad it gets worse right away.  Same deal with the left single row rear wheel bearing (and I was a long way from home on that one).

[Bagger John - #3785]

Some years ago, I put in a guy's (Shockbushing Gary RIP) custom made polyurethane dampers on both bikes, and it tightened both right up.  The OE rubber ones weren't really bad, just old (and I still have them, because I'm a pack rat).

I did similar with the first Tourer I owned. Actually bought two sets of Gary's dampers and several sets of bushings. I have a spare set of the former and at least two sets of the latter in my stash, against the day I'll need to replace either set of parts.

IIRC, he had some issues with early runs of his poly components and said issues were chronologued on this forum. Some comments were that the dampers weren't holding up. Have you ever had any trouble with yours, Jess?

[Jess from VA]

Have you ever had any trouble with yours, Jess?

No problem at all John.  Some of the early ones disintegrated into dusty crumbly pieces in short order.  Mine have been in there 10 years and are as new.  I hope to never replace them (before the dirt nap).

I had a car that broke multiple (OE rubber) motor mounts (allowing the engine to pop up and smack the hood) before going to polyurethane.  So I'm sold on that stuff.

[Tfrank59]

New dampers are so tight it is hard to get them to go in... how did you
check yours? I wiggled mine behind the backing plate the other day
and called them good, no rubber dust to speak of... I've thought that
new dampers have made that "lash feeling" on my bike better in the past...

-Mike

That's really all I did to check my dampers Mike what you did. I read where some aftermarket dampers were turning to crap I think Jess wrote about that and so I'm wary of buying anything but OEM dampers. I guess it's time to invest in a set if I can find some good ones

[Jess from VA]

Remember that early dampers (OEs) came in two parts, rubbers and metal inserts.  Beginning with '99 Interstates, they stared coming in single parts (for cheaper) with the inserts already in them.  Those are the ones you want (universal fit).  The two-part parts are probably long discontinued anyway.

Gary is long gone, and as far as I know, no polyurethane dampers are available anywhere.  It was only his first or second production run that were bad, all the others were great.

[Tfrank59]

Thanks!

[Avanti]

The last set of dampers the I ordered did not fit as tight as in the past, fell right in. I was not at all happen with them, I returned them.

[Tfrank59]

The last set of dampers the I ordered did not fit as tight as in the past, fell right in. I was not at all happen with them, I returned them.

can I ask who you ordered from?  I'll be sure and go with somebody else.

[nogrey]

Just a thought in another direction here. I recently acquired a 2001 Interstate. Went all through it doing necessary maintenance, tires, shocks, fluids, upgrades etc, etc, (you get the picture). Anyways, after all that I noticed while riding (especially if the road was bumpy) that she would “buck” a bit when I’d hit a bump and my wrist would let off the throttle slightly, then react and throttle back to maintain constant speed. So, to state it another way, there was a sort of lurching when I’d go off throttle to on throttle. Make sense? Way harder to describe than if I could show you. Anyway, that turned out to be a simple adjustment of throttle cable play. Mother Honda has an actual spec on throttle play (5mm if I remember correctly) and mine was greater than that. Adjusting it to spec completely cured that issue.

[Jess from VA]

Very good point!

I still remember how hard it was to keep a steady throttle riding down the middle of some railroad tracks over 1000 RR ties (not on a Valk, on a dirt bike, but the principle is the same).

[Avanti]

The last set of dampers the I ordered did not fit as tight as in the past, fell right in. I was not at all happen with them, I returned them.

can I ask who you ordered from?  I'll be sure and go with somebody else.


I ordered from westernhonda.com Scottsdale, AZ

[Ricky-D]

Loose dampers are not really a big problem as long as they are not degraded or fragmenting.  It's an error to assume loose dampers need to be replaced.

How to check the dampers. To check the dampers, insert the star and see how much rotation you can feel. Some would call that backlash.

A certain amount of individual looseness is necessary to allow for the star to be inserted. This is because of all manufacturing tolerances built into the damper system.

***

[indybobm]

i seem to remember that long ago someone made a chart to show the free play in each gear. Jack the back of the bike up and mark the rear tire in degrees. put the bike in each gear and measure the number of degrees of free play. Crude way of doing it i agree, but effective.

[Tfrank59]

i seem to remember that long ago someone made a chart to show the free play in each gear. Jack the back of the bike up and mark the rear tire in degrees. put the bike in each gear and measure the number of degrees of free play. Crude way of doing it i agree, but effective.

 that's interesting so you're saying in each gear assuming the free play is not excessive the rear wheel will rotate a certain number of degrees or something? I wonder where that chart is I've never seen it and I wonder who has that much time on their hands to make it

[Chrisj CMA]

Loose dampers are not really a big problem as long as they are not degraded or fragmenting.  It's an error to assume loose dampers need to be replaced.

How to check the dampers. To check the dampers, insert the star and see how much rotation you can feel. Some would call that backlash.

A certain amount of individual looseness is necessary to allow for the star to be inserted. This is because of all manufacturing tolerances built into the damper system.

***

Well. I guess a sloppy rear end is not a problem unless you demand or expect a bit more responsiveness. The ones I replaced yesterday looked great but they were loose. A fair amount of powdered rubber in the wells once I removed them. But they still looked good.

Put new ones in and immediately the ride improved.

So I agree with Ricky if you aren’t to picky about drivability. If you want a tight feeling rear end you change loose dampeners. I think it was at least five years when I switched from standard ones to the IS ones. Now that’s all what’s available and not that expensive. Worth changing every few years

[Cracker Jack]

I've had my first Interstate since 2003. I have had loose dampers but have never replaced one.

What I do when a set gets loose is cut  rubber shims and put in the pockets to take the slack out. Always works and never had a problem in many thousands of miles. A good source of shim material is the sidewall of a used tire.

Cut the shim the same size as the damper cross section. If it takes more than one, put in as many as possible to create a tight fit. Put the same amount of shims in each hole. It's important to put the shims on the correct side to take the load when decelerating (coasting). That would be the counter clockwise side.

There may come a time when a damper is too worn to use this procedure, it hasn't happened yet for me.

[hubcapsc]

When I was in high school, our little Japanese 100's and 125 enduro bikes had
dampers... we'd fill the looseness with silicone seal... it would be better
to get new dampers, but getting a tube of silicone seal was lots easier then ...
Doing nothing would result in needing a new rear hub  ...

-Mike

[Chrisj CMA]

The other way dampers can wear is the aluminum sleeves that the flange pins stick in can get worn so that the pins are very loose. This can enable the flange to wobble and wear stuff out real fast. Including the hub of the wheel as Mike said.

Not that expensive to replace every few years

[indybobm]

When i got my 2nd Tourer years ago, I had a bad surprise first time I did Final Drive maintenance. Previous owner forgot (I assume) to put the thrust washer back in. It took out the splines, drive flange, and rear wheel. It had the original dampers which have the aluminum inserts. The holes in the inserts where severely egg shaped. The drive flange chewed off most of the damper plate screws. Just remember, do it wrong and you (or the next person) has to pay the price.

[Chrisj CMA]

Had a patriot guard mission today. Very good shakedown test ride. With new dampeners the bike handled like a newer bike. Especially noticeable in the slow speed formations we tend to do where you have to really watch speed control. Lots of on the throttle and backing off throttle. So much smoother at the rear wheel. Also shifting was a lot smoother, not the actual changing of the gears but the reaction of the drive train was minimized. I have had this bike almost 18 years so I know it’s not my imagination.

If it’s been 4 or 5 years. Order a set of dampeners and change them next time the wheel comes off. It’s worth it.