TR650 chain tension seems really sensitive to load on the bike

[Coffee]

I kept noticing the chain tension on my bike was all over the place on my TR650.

Yesterday I went the store and bought some heavy items which I put on the bike, sat on it, and the chain seemed as tight as a guitar string.

Then I compared the distance of my TR650s counter sprocket from the swing arm pivot, and confirmed that distance is significantly larger than my 2006 TE250s CS to swing arm pivot... so that would be why my TR650 chain tension seems much more affected by how much weight is on my TR650...

This is just a 'heads up' in case others may not have noticed the situation.

 

[Lekolite]

On top of that, the chain tension appears to have quite the effect on how nicely the machine shifts.

 

[run-it]

Yep, mine came new WAY too tight, rear suspension wasn't working well not to mention the stress on parts. I "tighten" it to about 2" of play. I zip tied rubber material to the frame to protect it from the sag-gy chain, sort of a temporary solution that may be a long term solution if it holds up.

Counter shaft to swing arm pivot distance & unloaded swing arm angle are the culprits.

 

[Kawagumby]

The best way to make sure your chain doesn't get too tight is to compress the rear suspension to near full down, then allow some chain play at that point. I've been told by others who follow manufacturer's spec that this is not the best way to go, but I've ridden motocross, cross-country racing, etc. for several decades and it's the only way I've come up with to make sure I don't ruin the cases or countershaft and/or bearing, let alone bind up the suspension. You don't have to compress the suspension fully, you just need to get it down to where it gets close, then make sure you have a little slack to spare. On my dirt bikes I sit on the back end of the seat, bounce up on down to help settle the bike then bend over and check that chain tightness (becoming a challenge at 65) but you can also pull the bike rear down with tie-downs, come-along, whatever you've got handy to simulate heavy loads, landing off of jumps, etc.

 

[blakebird]

The tightest your chain is going to be is when the countershaft, swingarm pivot, and rear axle are in a straight line. As soon as the swingarm pivots either up or down, the arc it's moving in puts the rear axle closer to the countershaft (shorter distance = slacker chain).

When the suspension is unloaded (bike at rest, no rider) the swingarm is swinging thru an arc down, and the chain - if adjusted at that point - will be much tighter when a load is applied and the three items are closer to being in a straight line.

Chain tension should always be checked when that 'tightest geometry' is closer to being met.

My KTM's and XR's with the chain adjusted properly, look like the chain is draped over the rear sprocket and laying on the swingarm behind the pivot.
Perfectly normal and why I never check the chain tension unless my lard ass is sitting in the seat and bringing that 'tightest geometry' into play.

 

[FER QUILES]

The best way to make sure your chain doesn't get too tight is to compress the rear suspension to near full down, then allow some chain play at that point. I've been told by others who follow manufacturer's spec that this is not the best way to go, but I've ridden motocross, cross-country racing, etc. for several decades and it's the only way I've come up with to make sure I don't ruin the cases or countershaft and/or bearing, let alone bind up the suspension. You don't have to compress the suspension fully, you just need to get it down to where it gets close, then make sure you have a little slack to spare. On my dirt bikes I sit on the back end of the seat, bounce up on down to help settle the bike then bend over and check that chain tightness (becoming a challenge at 65) but you can also pull the bike rear down with tie-downs, come-along, whatever you've got handy to simulate heavy loads, landing off of jumps, etc.

I have tighten same way, just sitting rear side and leaving a spare 15mm

 

[Scutler]

I've noticed with riding 2-up, shifting into second is very abrupt. This must be due to a tight chain due to the extra weight.

 

[FER QUILES]

I've noticed with riding 2-up, shifting into second is very abrupt. This must be due to a tight chain due to the extra weight.

That reason make me leave 15-20mm, it depends passenger weight..

 

[Mike-AK]

If your chain is "tight as a guitar string" anywhere in the swingarm travel it is too tight. You are transferring force from the rear suspension through the chain and into your countershaft, potentially placing damaging loads on the bearings and case.

 

[PaulC]

If your chain is "tight as a guitar string" anywhere in the swingarm travel it is too tight. You are transferring force from the rear suspension through the chain and into your countershaft, potentially placing damaging loads on the bearings and case.

Shortly after my first service I noticed that all my gear changes were always noisy, it was like riding a old tractor with a crash box, to the point were I was actually thinking of getting rid of the bike I read in a couple of threads that the chain maybe the cause, so I tried backing it off and PRESTO silent gear changers have returned.
I don't know who said it first but THANKYOU This is a great forum. Live, Ride and Learn
Regards pc

 

[FER QUILES]

Somebody knows the mileage to replace all track system (sproket and chain) it could be 25.000km??. thanks

 

[Ogre_fl]

Replacement of chain & sprockets are driven by condition not distance.
Everyone has different results depending on maintenance, location and riding styles.

FWIW the chain on our bikes is junk.
I would be surprised if anyone gets it to 25,000 KM/15,500 miles.
I would not be surprised however to see a decent replacement chain go that far or further.

 

[nev..]

Somebody knows the mileage to replace all track system (sproket and chain) it could be 25.000km??. thanks

I think drive component life is like tyre life. Some people get great mileage out of the same tyres that other people need to replace far more often. I think a rider who opens the throttle at every green light and on the exit of every corner will eat chains and sprockets and tyres much faster than another rider on a similar bike who uses the throttle much more sedately. Unfortunately I am one of those who replaces chains sprockets and tyres often.

 

[Hansi]

Somebody knows the mileage to replace all track system (sproket and chain) it could be 25.000km??. thanks

Just changed mine at 9500 miles. Excessive wear on the o-rings. The chain did not like the sand and dust in Baja.

 

[FER QUILES]

Thanks guys, i do normal use.. 70% road, 100km/h and highway 130km/h- the rest 30% forest and gravel roads , and quiet trips. Last HOnda NX650 i used ti change it
between 20.000km and 25.000km..
if you do and extreme use 10.000 miles will be the rate..

 

[blacki]

I removed the rear wheel for the first time on my 12000km old Strada to change the tyre. I got a Conti TKC70. Great tyre! It gets tacky on the edges like a racing slick. OK in the wet and on dirt too. Anyway, I thought it was time to check the chain tension. It turned out to be 45mm at the front chain guard mount, just as the manual specifies. Then I sat on the bike and used a long screwdriver to reach down and check the tension. Tight as a guitar string.
I backed it off to 50mm, went away for the weekend and discovered the gear shifts were much smoother. Back in the garage, I got my wife to climb aboard as well, and the chain is again quite tight. Looks as if 55mm is about right. How could Husky get this spec so wrong?
At least there is no sign of chain wear or any tight spot so far. I expect it to go 25-30Mm, mostly on sealed roads. I'm about to buy a Cameleon oiler. I have one of these on my Daytona 955i, and it works very well. I don't use the SAE190 oil that comes with it though, it's a mess to clean off the back wheel. Chainsaw oil works as well, is cheap and easily obtainable, and washes off with soapy water. I'll probably do what I did with the Triumph: connect a brake fluid reservoir somewhere up the back of the bike, fill it with oil, forget about the chain for 5000km.
blacki

 

[nwrider1]

FWIW the most accurate way to determine the correct slack in a chain is to either remove the rear shock and position the swing arm so that the C/S is inline with the swing arm and rear wheel axle, or to compress the rear shock to achieve the same straight line. That will be the tightest point. I give it just a bit of slack at that point and then check the distance between the swing arm and the chain when the bike is either on the side stand or center stand (if you have one) and take a measurement at a marked point for reference and future adjustment.

 

[drzcharlie]

I have been using ratchet straps for years (on every bike that I have had with a chain) to pull my swing arm and rear axle up until it aligns (straight line) with the center of the counter sprocket. Once those points are in line just snug the chain giving it about 1/8" to 1/4" of slack up and down then tighten the axle enough so it doesn't move and then release the ratchet strap.

When you are doing this and the rear axle and the center of the counter sprocket become aligned, this is the point where the chain will be the tightest it will ever be, loaded or not.

 

[Mark_H]

I have been using ratchet straps for years (on every bike that I have had with a chain) to pull my swing arm and rear axle up until it aligns (straight line) with the center of the counter sprocket. Once those points are in line just snug the chain giving it about 1/8" to 1/4" of slack up and down then tighten the axle enough so it doesn't move and then release the ratchet strap.

When you are doing this and the rear axle and the center of the counter sprocket become aligned, this is the point where the chain will be the tightest it will ever be, loaded or not.

The perfect solution and correct way to do it !
Unfortunately, as previously stated, the details in the 'manual' are incorrect and can lead to an overtight chain and associated problems.

A friend of mine has a Strada which he rides as an all round bike, used on Fire Road type trails and long touring runs too. For several months he has been complaining to me about a 'strange' clutch problem, or so he thought.

It appeared to occasionally slip or do strange things, but only when cruising at high speeds in 5th gear. It did not happen at all when he was out on the trails.
Whatever we tried we could not get it to slip or play about in any other gear or situation and the bike will wheelie etc with no problems.
The clutch has been apart, inspected and nothing wrong was found. Modifications were considered with a GS650 arrangement etc but not carried out.
The problem remained and had us all really stumped......

Finally the issue has been solved and found to be simply an overtight chain - which was actually adjusted to the manual specs.

The reason the clutch seemed to only slip in 5th gear high speed cruising was that in all other situations, fire trails etc, it was always only bike and rider, but when cruising and touring the bike was fully loaded, two up with topbox and panniers.
The extra weight caused the chain to be overtight and strange things to happen under full load in 5th gear.

The owner is lucky not to suffered serious damage, but at least now we know and can use Charlie's Ratchet strap method to get it right.

 

[blacki]

OK, to those who have lined up the countershaft, swingarm pivot and rear axle by whatever means, what did the chain slack end up being when the bike was back on the sidestand, the figure that SHOULD have been in the manual?
blacki