Honda CBR 1000RR Forums banner
1 - 9 of 9 Posts

·
Registered
Joined
·
31 Posts
Discussion Starter · #1 ·
After 5 months of building my bike from ground up I had the chain fly off today. Messed the plastics and frame up pretty good but thankfully no hole in the block, just broke the sprocket guard. Bike is stretched but nothing too crazy and it also has -1 + 2 combo on it with a .530 rk riveted chain. My question is what are some things I could do to insure that if the chain comes flying off again I can add a little protection so I won’t have to worry as much about putting a hole in the block along with slimming down the chances of the chain even coming off again. I was told to run the chain tighter but some people say looser with it stretched. I just know I do not want to put another hole in the block so any recommendations would be appreciated! Thank you!
 

·
Registered
Joined
·
31 Posts
Discussion Starter · #3 ·
There is no protection from a broken chain. It's catastrophic due to the forces involved.

How much did you stretch your bike? What steps did you take to ensure front/rear sprocket alignment and proper chain tension?
Unfortunately that was my thoughts as well.
And it have about an 7 inch stretch, and I use a micrometer on the rear chain adjuster bolt to axel block to get it as close as possible to straighten back wheel up and I stay around a half-inch slack in the chain. And as far as doing a front and rear sprocket alignment I have not taken any steps towards that because I’m not informed on that much.
 

·
Registered
2016 CBR1000RR
Joined
·
104 Posts
Hey bro. I don’t have experience with stretched bikes but… the chain slack sounds “tight” @ 1/2” (that’s about 12-13mm) Spec on a stock bike is 25-35mm. That’s based on standard wheel base. I may consider contacting the manufacturer of your stretch kit and asking some questions on their recommendation on chain slack. Also, with the addition of the aftermarket parts required to complete the stretch I don’t know if I would trust the micrometer method for aligning the rear wheel in your setup. I mean I’m sure it will get you close. There is a tool you can get that clamps on the rear sprocket to help you align the rear wheel. I don’t know if that will be the fix for your problem or if there is a more technical way to align it that someone can advise…and should go without saying imo that you should not even consider reusing that chain or either sprocket at this point. Start with new parts and be sure everything is aligned and tensioned properly. Good luck my bruddah
 

·
Registered
Joined
·
31 Posts
Discussion Starter · #5 ·
Hey bro. I don’t have experience with stretched bikes but… the chain slack sounds “tight” @ 1/2” (that’s about 12-13mm) Spec on a stock bike is 25-35mm. That’s based on standard wheel base. I may consider contacting the manufacturer of your stretch kit and asking some questions on their recommendation on chain slack. Also, with the addition of the aftermarket parts required to complete the stretch I don’t know if I would trust the micrometer method for aligning the rear wheel in your setup. I mean I’m sure it will get you close. There is a tool you can get that clamps on the rear sprocket to help you align the rear wheel. I don’t know if that will be the fix for your problem or if there is a more technical way to align it that someone can advise…and should go without saying imo that you should not even consider reusing that chain or either sprocket at this point. Start with new parts and be sure everything is aligned and tensioned properly. Good luck my bruddah
Thanks for the reply and info bro!! At 1/2 inch it definitely is very tight but dealer told me to run it like that even tho I thought that sounded off lol. I’ll probably go with an inch of slack as the frame was custom welded and idk who the manufacturer would be. Already got new sprockets and chain on the way so maybe this go around I’ll be good 🙃 I’ll have to look into an alignment tool for sure. Thanks again!
 

·
Registered
Joined
·
176 Posts
1/2 inch is way too tight I'm not surprised it broke. It should be even more slack than standard 40-50mm at least with a longer swing arm. Also look at chain adjusters like Lightech or Bonamici Racing Chain Adjusters, the click adjustment means you can get them very accurately aligned.
 

·
Registered
Joined
·
31 Posts
Discussion Starter · #7 ·
1/2 inch is way too tight I'm not surprised it broke. It should be even more slack than standard 40-50mm at least with a longer swing arm. Also look at chain adjusters like Lightech or Bonamici Racing Chain Adjusters, the click adjustment means you can get them very accurately aligned.
Thanks for the reply, I wonder why there’s so much bias info between running them tighter and looser? Ive been told that slack on a stretched bike is way more prone to chain coming off and then too tight can damage the trans gear along with snapping the chain as you’ve mentioned. And yes sir.. I’ve actually got a lightech chain adjuster on the way with the sprocket combo. About how many mm would you recommend with about a 7 inch stretch
 

·
Registered
Joined
·
176 Posts
Where is the said bias? As the swingarm moves up via compression of the rear shock it pulls the chain tighter. This is exacerbated by a longer swing arm. The likelihood of a chain coming off from being too slack is very low compared to pulling the output shaft out the casing. I am honestly surprised it broke a 530 chain before it broke the transmission. You want as I mentioned earlier 40-50mm. If you have a buddy get them to push down compressing the swing arm as much as possible and watch how tight the chain gets as he bounces his weight on it.
 

·
Registered
Joined
·
31 Posts
Discussion Starter · #9 ·
Where is the said bias? As the swingarm moves up via compression of the rear shock it pulls the chain tighter. This is exacerbated by a longer swing arm. The likelihood of a chain coming off from being too slack is very low compared to pulling the output shaft out the casing. I am honestly surprised it broke a 530 chain before it broke the transmission. You want as I mentioned earlier 40-50mm. If you have a buddy get them to push down compressing the swing arm as much as possible and watch how tight the chain gets as he bounces his weight on it.
Unfortunately I’ve heard from Honda service, and a tuning/repair shop to run tighter. Deep down I knew that I needed more slack tho but I put my trust in them as this is my first stretched bike 🤣 thanks for all the great information, I’ll definitely make sure there is at least 40-50mm.
 
1 - 9 of 9 Posts
Top