2015 Honda CBR600RR - chain slack ?

[Ndx]

Hi Friends,

So I’m trying to adjust my chain slack, and I’m confused YouTube videos are saying one thing and official service manual is not very clear.

My take is:

I measure chain from “relaxed” position from center of the chain, to the top of the swingarm.

I should have 30-40mm play

I do not push down on chain ( as some of the sites and YouTube videos say ? )


Anyone would interpret this differently ?

Thank you

 

[The_Sheriff]

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I rotate the wheel until I find the tightest point in the chain midway between sprockets. Then, push up just as the diagram shows and take your measurement. I stop pushing upwards when I see the upper part of the chain begin move. The chain will tighten when you sit on the bike. Just so you know.

 

[Ndx]

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I rotate the wheel until I find the tightest point in the chain midway between sprockets. Then, push up just as the diagram shows and take your measurement. I stop pushing upwards when I see the upper part of the chain begin move. The chain will tighten when you sit on the bike. Just so you know.

Thx, so just light up motion not really push because as soon as you feel it “stopping” it’s robbing the slack from the top …

 

[2strokeNorthstar]

I always interpret it as the gap until stiff. Not the slack from gravity only. I also usually just use the 2 figer gap. Had a cbr600 f4i and many dirt bikes.

 

[IndyIan]

On the dirt bikes I go with the measurement but with pushing up and down hard enough to flatten out the top of the chain. I dislike slack/driveline slop. I do check that there is some slack with the chain at its tightest with the suspension compressed.

 

[2strokeNorthstar]

On the dirt bikes I go with the measurement but with pushing up and down hard enough to flatten out the top of the chain. I dislike slack/driveline slop. I do check that there is some slack with the chain at its tightest with the suspension compressed.

There definitely is some room for preference. Worrying about a few mm one way or another is way more than most everyone else does.

 

[twX]

You should press down on the chain to get the lower measurement. A moderate amount of force with a single finger should be enough.

As the chain ages, some sections of the chain will stretch more than others. Try to ensure that the tightest part of the chain isn't much tighter than 30 mm, and that the loosest part isn't much looser than 40 mm. If this isn't possible, it's probably time for a new chain.

 

[Ndx]

You should press down on the chain to get the lower measurement. A moderate amount of force with a single finger should be enough.

As the chain ages, some sections of the chain will stretch more than others. Try to ensure that the tightest part of the chain isn't much tighter than 30 mm, and that the loosest part isn't much looser than 40 mm. If this isn't possible, it's probably time for a new chain.

Seee if you could back this up with something
on Yamaha it clearly states to push down

Lower + Top combined ?
It’s not stated in manual so that’s why I’m looking if this accurate or not

Thx

 

[Ndx]

I always interpret it as the gap until stiff. Not the slack from gravity only. I also usually just use the 2 figer gap. Had a cbr600 f4i and many dirt bikes.

What is the two finger gap ?

 

[Bonz]

Keep in mind, the chain does not stretch, the pins and links wear, which creates minute differences in tolerances and they add up to a longer chain. The metal doesn't stretch.

I like mine adjusted so there is 1.5" of lift from the relaxed position. Not an exact science, however, that feels like a correct amount of slack and the measurement I just took confirms it.

It has to accommodate the swingarm compressing and extending although not to the same extent as a dirtbike. I get 30,000+ miles out of a chain on a ZRX 1200 that's making 40 more ft/lbs of torque than a 600. It's far more beneficial to a chain to be on the slack side than on the tight side. That's why I run it where I do.

 

[JWC86]

No need to make this complicated. Push down moderately(enough to take out all slack) measure, push up the same, measure. The difference in the measurements is your slack.

I used to like might on the tight side just figuring that would be better but I’ve learned over the years that a slightly too tight chain can wear out counter shaft bearings early or I’ve even see it crack engine cases. On the other hand a slightly too loose chain might just be a little noisy so I run my chains on the looser side of the spec.

If you really want to know for sure support the bike so the rear wheel is off the ground and remove the rear shock, move the swing arm through the whole travel and make sure the chain isn’t getting tight.

 

[Bonz]

No need to make this complicated. Push down moderately(enough to take out all slack) measure, push up the same, measure. The difference in the measurements is your slack.

I used to like might on the tight side just figuring that would be better but I’ve learned over the years that a slightly too tight chain can wear out counter shaft bearings early or I’ve even see it crack engine cases. On the other hand a slightly too loose chain might just be a little noisy so I run my chains on the looser side of the spec.

If you really want to know for sure support the bike so the rear wheel is off the ground and remove the rear shock, move the swing arm through the whole travel and make sure the chain isn’t getting tight.

No need to make this complicated? I'm not being malicious here, only having a little fun.

You've suggested pushing down on the chain, then raising it up, then doing a math problem (albeit a simple one) to find the amount of slack. Then raising the rear wheel off the ground, taking off the shock and moving the swing arm through its travel in order to really know for sure the chain isn't tight.

He answered his own question in the first post, from the relaxed position measure from the center of the pins to the center of the pins once the chain is lifted.

From another post, with respect to interpreting as 1.5 in of slack from pushed down position to pulled.... 1.5 in of slack from the pushed down position to the lifted position feels too tight for my liking and I don't think is good for the long-term component wear of the whole drivetrain which includes countershaft bearings that are not a good thing to wear out prematurely. Again, a slightly loose chain is better than slightly tight or tighter. If a manufacturer suggests 1.5 in from push down to lift it up, I suspect they're trying to eliminate as much chain noise as possible, Lord knows there are probably some people that come back to the dealership after a few rides and complain about the chain noise.
 

 

[Randol]

All good advice above. I don't have anything to add. I try to keep mine close to spec., (Dirt and street) probably worry about it too much.
Hopefully this does come across as an advertisement, but I bought one of these recently. Incredibly easy to use, cheap, and accurate enough for chains.

https://www.motionpro.com/product/08-0674

I have been using Bel Ray super clean chain lube for 15 years, love the stuff
About once a season I'll scrub down the chain with mineral spirits.

 

[twX]

Seee if you could back this up with something
on Yamaha it clearly states to push down

Well, my Suzuki manual makes it clear that the chain should be pushed down.

On the other hand, my Honda dirt bike manual has a diagram just like yours, where it isn't made clear. Still, I push down. If you're concerned that pushing down will result in the chain being set too tight, set it closer to 40 mm than 30 mm. What difference do you measure between the two methods?

 

[ARCOgraphite]

Dont take up too much. Or that will be the end of the bearing behind the trans sproket on the first jounce

 

[02SE]

I always like the chain on the loose end of the tolerance. With a new bike, I check chain slack through the range of motion of the swingarm to determine when the chain is tightest, and from then on use a chain slack figure which accommodates that tightest point. From then on I can easily check and set slack at the midpoint between the sprockets with the bike up on a rear stand. The AMA ( back when that was the top USA Roadracing program) Roadracing teams (where I learned this method as an amateur racer sharing time with them in the pits) didn't want piano wire tight chains, and having ridden bikes with chains which are too tight, I don't want that either.

 

[Bonz]

Well, my Suzuki manual makes it clear that the chain should be pushed down.

View attachment 296966

On the other hand, my Honda dirt bike manual has a diagram just like yours, where it isn't made clear. Still, I push down. If you're concerned that pushing down will result in the chain being set too tight, set it closer to 40 mm than 30 mm. What difference do you measure between the two methods?

Suzuki is calling for a pretty tight chain, unless there's geometry that's radically different in swingarm travel compared to all other bikes out there. I would go looser than that unless there's an issue with clearance on the swing arm or other components. It's like if there's 100 guys in a bar saying a catch is a catch in a football game, it probably is. Same thing holds true for millions of folks adjusting a chain in the history of motorcycles. They'd probably say looser rather than tighter, 1.2 from pushed down to pulled up seems a bit tight.

 

[Bonz]

All good advice above. I don't have anything to add. I try to keep mine close to spec., (Dirt and street) probably worry about it too much.
Hopefully this does come across as an advertisement, but I bought one of these recently. Incredibly easy to use, cheap, and accurate enough for chains.

https://www.motionpro.com/product/08-0674

I have been using Bel Ray super clean chain lube for 15 years, love the stuff
About once a season I'll scrub down the chain with mineral spirits.

That's a nice tool, glad you like it. Definitely works for its singular purpose. I took a tape measure, measured slack from resting to pulled upward, but didn't measure to the swingarm which seems silly as it's pretty obvious if it's an issue being too loose. I don't know a manufacturer that gives a specific measurement to the swingarm, but could be wrong. Used the same tape measure the next day for a project around the house. Motion pro has great tools, but a lot of them are a tool in search of a need, IMO.

 

[2strokeNorthstar]

What is the two finger gap ?

There is a point on the swing arm where you are supposed to measure it according to the manual. Usually the top at the rear of the plastic slider/guide. 2 fingers is usually within the range of adjustment and much easier than trying to use a ruler or something. Can't use this strategy on every bike of course.