2019 gt chain tension.

[whistler]

On 5/11/2020 at 9:41 AM, Matt 2703 said:

so, who is right, the owners manual or the main dealers?

In this particular case, I'd err on the side of the manual.  As BBB stated in his earlier post, 35-45mm while on the center stand is good.  My owner's manual and service manual also state the same amount of slack.  Also as others have stated elsewhere, a little bit loose is always better than a little bit tight.

I made a crude homemade measuring jig out of a 2" x 3/8" plywood strip.  Cut the overall length just short enough to hold it just off the garage floor, picked a spot about halfway between the front and rear sprockets and pulled the chain down until it stopped.  Then using a chain link pin as a reference, I scribed a pencil line across the plywood.  From that line, I measured up to 35mm and scribed another line across the plywood.  From THAT line, I measured another 10mm and scribed another line across the plywood. 

To use, just pull the chain down to the bottom index line, hold the plywood strip still, and then pull the chain up toward the upper 35 and 45mm index lines.  As long as the chain's link pin falls between those 2 upper index lines, you're good.  if the chain doesn't make it to the 35mm line, the chain's too tight.  Conversely, if the chain's upper limit is beyond the 45mm line, it's too loose.  Adjust the chain tension until your link pin reference falls between the 35 and 45mm marks, tighten things down, and go ride.  No need to overthink things.

This is what's worked for me over the last several bikes and 173,000 miles.  As always, YMMV.  Happy riding!

[edgarjessop12]

Well after some 32 bikes and 73 years old, I have never used a manual in my life. Rear suspension is different on every bike. I always measure after adjustment on the centre stand, with the bike straight up and on the GROUND with me sitting on it, obviously you need a second person, or lean over and check yourself and then readjust as necessary. The difference from the setting on the centre stand is massive and if you carry a pillion it is even more tight. Too loose is better than too tight, especially if you thrash the bike hahaha. I get about 20,000 miles from my chain, and aways fit new sprockets with my new chain. But keeping it clean and greased goes a long way to having a big milage from a chain.

Enjoy everyone and stay safe.

Cheers Edgar Jessop.

[jamespansbro@yahoo]

I agree that a little loose chain is better than a little tight. I just traded in my 2011 Suzuki gsx1250 for my new tracer900. I had the original chain and sprockets with 56000 miles on them and not ready for replacement

I cleaned and waxed the chain every 200 miles and used dupont degreaser and chain saver.I believe riding conservatively puts less strain on the chain vs

 riding like a maniac!

[kilo3]

3 minutes ago, jamespansbro@yahoo said:

dupont degreaser and chain saver

Love that stuff.

[betoney]

9 minutes ago, jamespansbro@yahoo said:

 riding conservatively puts less strain on the chain vs riding like a maniac!

Sshhh! - Enough of that nonsense.  CP3 + riding conservatively = ☹️

[roadrash83]

Chains, tires and brake pads are consumables!  The more you consume the more fun you have! 👍                                                                                                                                                                           

[trevinator]

i have always just tightened my chains to about an inch of slack. you only need enough slack so that the chain doesnt fully tighten while the swingarm pivot is aligned with the sprocket centers, because if that happens, you put lateral load on the engine output shaft and will stress the frame, and at that point you will either stop the suspension movement or break hard parts.

[betoney]

17 minutes ago, trevinator said:

i have always just tightened my chains to about an inch of slack. you only need enough slack so that the chain doesnt fully tighten while the swingarm pivot is aligned with the sprocket centers, because if that happens, you put lateral load on the engine output shaft and will stress the frame, and at that point you will either stop the suspension movement or break hard parts.

True, you could always disconnect the rear shock and elevate the rear tire so the output shaft, swingarm and rear axle are level to get the truest idea of the tightest point, so you would always have that reference figure.  Personally, from that tightest measurement, I would add 10mm slack.

[StealthAu]

On 6/16/2020 at 8:06 AM, betoney said:

True, you could always disconnect the rear shock and elevate the rear tire so the output shaft, swingarm and rear axle are level to get the truest idea of the tightest point, so you would always have that reference figure.  Personally, from that tightest measurement, I would add 10mm slack.

You want 1 to 3% of the distance between front and rear sprocket centres. Not a fixed value. 

[betoney]

12 minutes ago, StealthAu said:

You want 1 to 3% of the distance between front and rear sprocket centres. Not a fixed value. 

Yep, 10mm is around 2%

[StealthAu]

6 hours ago, betoney said:

Yep, 10mm is around 2%

It  might change a bit on the later models with longer swingarms. 

I checked mine a while back, when I changed the shock spring. I can't find a record of the numbers, but stock specs on the centre stand were right.

When doing this, I set the slack to 3% with everything lined up. Put the shock back in, let the rear wheel hang and measure slack. this value becomes the point where you would adjust your chain. 

Next, remove the shock again and line it all up. Set to 1% and reassemble. Measure the slack again with the rear wheel hanging. This value is what you set it to when adjusting.  

 It sounds like a lot of work, but if you already have your shock out, it'd add 5-10 minutes to the job and provides accurate reference points. 

[Toddtr]

Some of you are making way to big of a deal about the chain. Making jigs and all that stuff, just keep it simple.....use a tape measure to check for proper slack. You don’t need help and if you can’t do this simple procedure then you should take it to a mechanic, it’s just not your thing. 

[kilo3]

1 hour ago, Toddtr said:

Some of you are making way to big of a deal about the chain. Making jigs and all that stuff, just keep it simple.....use a tape measure to check for proper slack. You don’t need help and if you can’t do this simple procedure then you should take it to a mechanic, it’s just not your thing. 

Motorcycle maintenance is like lawn care. The older you get, the more time you have to to putz about nothing that matters.

[skipperT]

12 hours ago, StealthAu said:

It  might change a bit on the later models with longer swingarms. 

I checked mine a while back, when I changed the shock spring. I can't find a record of the numbers, but stock specs on the centre stand were right.

When doing this, I set the slack to 3% with everything lined up. Put the shock back in, let the rear wheel hang and measure slack. this value becomes the point where you would adjust your chain. 

Next, remove the shock again and line it all up. Set to 1% and reassemble. Measure the slack again with the rear wheel hanging. This value is what you set it to when adjusting.  

 It sounds like a lot of work, but if you already have your shock out, it'd add 5-10 minutes to the job and provides accurate reference points. 

But why do all this work? Not including the early models, the published spec for the later 900GT is fine. 35-45mm while on the center stand.

-Skip

[StealthAu]

27 minutes ago, skipperT said:

But why do all this work? Not including the early models, the published spec for the later 900GT is fine. 35-45mm while on the center stand.

-Skip

 

1 to 3% slack at point of maximum tension is the requirement from an engineering perspective. 

The measurements in the book are a reference point derived from this. Sometimes there are translation errors or whatever else resulting in the info in the book being wrong. As per your example. 

The specs for the GT are right, but I wouldn't know this if I didn't check. When I change the oil, I don't just poor in the specified amount and assume it is right, I check the sight glass..