chain stretch question

[Punjistick]

Ok, as some of you know I just bought a new 06 gsxr 750. I was performing some of the 600 mile maintenance today and when I got around to the chain I noticed there was a good 5 inches of play or so it seems. I've got plenty of room to slide the axle back and tighten it up and chances are it just stretched a bit. Is this normal for a new chain? It would make sense for a new chain to stretch a bit I would think, but I just want to make sure it's not going to part on me.

[ZX-12R]

Did you mean to say 5 inches or 0.5 inches? If you did mean 5 inches, how are you measuring the play in the chain?

The general rule of thumb for chain play is about 3/4 inch between lightly pushing it down and lightly pulling it up on the lower part of the chain (the section that is heading towards the wheel).

[TTD]

Stretching does not equal Loosening.


In other words, verify first if your chain is "stretched". Pull the chain directly backwards at the very furthest part back of your rear sprocket.

If you can pull the chain off the sprocket enough so that half the height of the sprocket tooth is visible... the chain is junk. Adjusting won't do shit.

Ideally, you should barely be able to pull or wiggle the chain at this spot. It should be "locked" into the sprocket basically.

Now... if the chain is nice and tight... then you can go about adjusting it. I use the "three finger" method at the bottom middle of the chain for a good starter.

Basically, the thickness of three fingers is about how much the chain should move up and down at this spot. That much movement should eliminate "slop", but allow the suspension to work effectively.

NOTE: The 3 fingers includes the chain thickness. So it's from the top of the chain when moved up... to the bottom of the chain when moved down. So the center of the chain is moving much less than 3 fingers width.

[Punjistick]

It probably had just become loose and not stretched. I estimated about 5 inches of play (up and down movement in chain between the front and rear sprocket).

I'm going to count out 21 pins when the chain is tight and as long as it is within 319.4 mm (12.57 in) according to the service manual, it should be fine.

I usually clean, lube, and check the chain every 600 or so miles and I was just a little concerned since I've never had a chain be that loose after only 600 miles. This is probably one of those overly paranoid moments like FireFly has all the time.

[TTD]

Another thing to check is the alignment method on your bike.

On my CBR600rr (2003 version)... they have a crappy setup.

I was adjusting my chain after every track day.

I then realized that my chain adjusters were actually spinning.

One small piece of duct tape on each adjuster solved the problem. I have now gone 3 track days and the chain hasn't loosened a bit.

Note. Tightening your axle nuts has nothing to do with this. Your axle nuts do NOT keep your rear tire in alignment. Your adjusters do. Remember, your axle is parallel to the force causing your chain to loosen. Your chain adjuster are perpendicular to the force (which is your motor pulling the rear sprocket forward)

Good luck.

[union]

5 inches of play is a lot. Id think the chian would be starting to slip off at this point. Are you maintaining your chain? 600 miles isnt a lot of miles but you should always take a quick look at the chain each time you ride. If its dry its life cant be substaintially reduced.

On the positive side your going the round about way to a mod a lot of people have been doing to the gsxr 1k. One of my friends is testing one and I guess one of the things to do is add a link or two and adjust the wheel as far back as you can. I dont know if this translates to the 750 but I guess it makes a big difference on the 1000.

[Billy]

Hey Alex,

Five inches of free play on a chain???? Dude if it's that loose it would have flown off. Did you mean half an inch?

What I usually do is I have 1 inch of free play on the chain. Basically you push on the lower chain that is going towards sprocket in the middle of that segment, and push up and down. Measure how much it moves.

When I put my new chain on my bike last summer I think i had to make a slight adjustment a week or so after I installed it. Probably because the chain got broken in.

[Punjistick]

yeah there was a good 4-5 inches of play in the middle. It was so loose that it looked like it would touch the ground. I counted out 21 pins and it was within spec according to the manual. I just tightened it up and had about 5 "marks" from the end of the swingarm so it's not maxed out which is good.

It made a huge difference. I was thinking to myself that the bike seemed to have a lot more power and then the next thing I knew the front wheel was up in the air.

[JeffL]

So after 600 miles on a new bike, you've already almost maxed out the adjusters?

[double agent]

sounds to me that your adjustments just got loose, thats if Im reading your post right. new bike + 600 check up= chain loose?
its possible.

[KB]

Sounds like you need to look at how you're measuring the chain tension!!

The manual will illustrate the proper technique.

KB

[FireFly]

If you have read any of my post, you know im OCD about this kinda stuff. I check & lube my chain every 200 miles/Clean & relube every 5/600 miles. If you only have 600 miles on the bike, 5 inches of play sounds Really strange. If you have to go to the end of your adjusters to get the right tension, i would go back to dealership & tell em to give you a new chain on the spot/ no questions asked. Did you notice any chain slap when you rode like that??35 Racer's 3 finger method is cool. im gonna do that from now on. I usually use a gauge and dont allow the freeplay on my chain to go beyond 30mm. (between 25 & 30mm). Also , you probably already know this but just in case, be careful not to overtighten the chain. It'll stretch quicker and the lifespan will dramatically decrease. keep in mind the tension of the chain while you are sitting on the bike too. BTW: Nice Bike bro. How is it? do u like the gixxer 750?

[Punjistick]

maybe I didn't explain it right. The adjusters are not maxed out. They are about 6 notches from the end of the swingarm which puts it just about dead center after I tightened it up (using the three finger width of play). What was strange was how much slack was in the chain even though the adjusters were tight when I first noticed it. The dealer probably just set it too loose. It's all good now though.

FireFly, I do like the 750 a lot. It's nice to have something new and it is easier to throw around then my old gsxr 600. The only thing I don't like are the tires that come on it. I haven't pushed the tires (Bridgestones) too hard though mainly because of the colder temps and I don't like to take it to the max on the streets. Only time will tell I guess. I rode my brother's cbr 600 which has pilot powers on it and it's like night and day.