140/70-17 rear tire wouldn't fit after new chain + sprockets..

[Lil_Green_Demon]

Does anyone know why?
The chain is an RK 520. The sprockets are 15T front and 45T rear.
The mechanic who did the work said that the new chain being tighter pulled the tire closer to the bike and causes contact. I could actually see the contact point. The mechanic also told me that once the chain loosens up a bit, the tire will fit again. I have a 140/60-17 Shinko tire on now.
So does anyone know why? Did I get the wrong chain + sprockets combo somehow? I didn't have this problem in the past with the 140/70 tire size.

[Boom King]

Doesn't sound like something is right. That would have to be pretty tight no? Even if it loosened up enough to have the tire fit in again, how much room would there be to avoid rubbing when going over rough surfaces?

[Lil_Green_Demon]

Originally Posted by Boom King

Doesn't sound like something is right. That would have to be pretty tight no? Even if it loosened up enough to have the tire fit in again, how much room would there be to avoid rubbing when going over rough surfaces?

Honestly, I have no idea.

[DmbShn41]

Anyway to confirm you have the same amount of links on the new chain as you did with old chain? Did you have the same sprocket set up as before?

Adding the 15T up front will increase the overall circumference the chain travels, so if you have had a specific mark you had tightened to before, then changed sprocket, your new mark will be ahead of the previous mark.

May have to add a link or two on chain.

[Motofool]

Originally Posted by Lil_Green_Demon

Does anyone know why?
.......

Your mechanic is the problem, Umar.

The chain runs parallel to an aligned rear tire; hence, the forward relocation of the wheel cannot affect the distance between the sides of the chain and tire.

If the longitudinal movement of the wheel cannot be adjusted anymore, the length of the new chain is incorrect (106 links are OK for 15/45 sprockets).
If the new chain has no slack now, it will destroy itself (and maybe something else) soon.

If it can be adjusted, then you need to do what this article describes:
http://www.motorcyclistonline.com/ho...rcycle_wheels/

[tfkrocks]

Sounds like an incompetent mechanic. I put on a 15T sprocket on my bike with stock chain with a 140 rear tire and it's just fine.

[Alex]

Originally Posted by Motofool

Your mechanic is the problem, Umar.

The chain runs parallel to an aligned rear tire; hence, the forward relocation of the wheel cannot affect the distance between the sides of the chain and tire.

What I got from his post was that the tire wasn't rubbing the sides of the swingarm, but was touching the center of it. That doesn't sound like an alignment issue, but is more a combination of too large a tire and a chain that is at its shortest when new. The 15-tooth sprocket will pull the rear axle slightly forward compared to the 14-tooth.

Different brands/types of tires that are nominally the same specified size, can sometimes be slightly different. Is this 140/70 the exact same type of tire you have used before?

[Lil_Green_Demon]

Yeah, it's the same rear tire as before. It's the Bridgestone Battlax BT45.

[rojoracing53]

Please find a new mechanic because yours has cut your chain to short me thinks and is probably blaming other **** so they don't have to buy you a new chain
how many links does this new chain have?

[Lil_Green_Demon]

@rojoracing53 I'm sure you're right. I don't have time right now to set aside to count the links, but I'm sure I need to find a new mechanic.
I actually went to a place called Langston Motorsports in Perris, CA. Anyone close by should either avoid this place or hope they don't encounter the young man who did the work on my bike.

Thanks for the responses, gentleman. I'm sure it has to be something along the lines of the mechanic cutting the chain shorter than 106 links. I've had a 140/70-17 tire installed before and didn't encounter this problem, albeit my chain probably only had 3000-4000 miles on it at the time.

[Vintage Smoke]

Originally Posted by Lil_Green_Demon

@rojoracing53 I'm sure you're right. I don't have time right now to set aside to count the links, but I'm sure I need to find a new mechanic.
I actually went to a place called Langston Motorsports in Perris, CA. Anyone close by should either avoid this place or hope they don't encounter the young man who did the work on my bike.

Thanks for the responses, gentleman. I'm sure it has to be something along the lines of the mechanic cutting the chain shorter than 106 links. I've had a 140/70-17 tire installed before and didn't encounter this problem, albeit my chain probably only had 3000-4000 miles on it at the time.

Well....no. You had a used BT45 and a used chain before and now you have a Shinko so it is NOT the same tire. As Alex said: Different brands/types of tires that are nominally the same specified size, can sometimes be slightly different. You changed brand and if the old tire was a little close before, the new tire may be just slightly taller. Add this to a new chain that has not loosened up at all yet and you get the rubbing. Don't be so quick to blame the mechanic. Besides....you are installing a non stock tire size and larger than stock sprocket size so clearance issues are definitely something that you risk.

- Did you buy the parts through them or did you buy the stuff on line and bring it to them to install?
- Did you research whether or not this combo would work before you decided on it?
- Did you look at Shinko's and Bridgestone's data on their tires to see if there was any difference in the diameter of each tire?

If you simply had a mechanic install a NON STOCK tire, chain, and sprocket on your bike, at your request, without doing your own due diligence to make sure it would work, then why would the mechanic and the shop he works for suddenly be crap and deserving of getting bashed on the internet?

[rojoracing53]

Originally Posted by Vintage Smoke

Well....no. You had a used BT45 and a used chain before and now you have a Shinko so it is NOT the same tire. As Alex said: Different brands/types of tires that are nominally the same specified size, can sometimes be slightly different. You changed brand and if the old tire was a little close before, the new tire may be just slightly taller. Add this to a new chain that has not loosened up at all yet and you get the rubbing. Don't be so quick to blame the mechanic. Besides....you are installing a non stock tire size and larger than stock sprocket size so clearance issues are definitely something that you risk.

- Did you buy the parts through them or did you buy the stuff on line and bring it to them to install?
- Did you research whether or not this combo would work before you decided on it?
- Did you look at Shinko's and Bridgestone's data on their tires to see if there was any difference in the diameter of each tire?

If you simply had a mechanic install a NON STOCK tire, chain, and sprocket on your bike, at your request, without doing your own due diligence to make sure it would work, then why would the mechanic and the shop he works for suddenly be crap and deserving of getting bashed on the internet?

It all depends on the surrounding circumstances but I would think a good mechanic would have just said your chain is to short for this setup and you should get a longer one. The tire rubbing on the center of the swingarm and the mechanic recommending the chain just needs to break in a bit is just stupid. If its that close to the swingarm then you must be at the front of your axle adjustment and could really use a 2 link longer chain.

**** gets lost in translation all the time between mechanic and rider. Maybe I assumed to much we I assumed he was like so many other crappy mechanics I've heard about trying to shift the blame after they made a mistake that's going to cost them $.

[bruce71198]

Picture?

[Lil_Green_Demon]

Originally Posted by Vintage Smoke

Well....no. You had a used BT45 and a used chain before and now you have a Shinko so it is NOT the same tire. As Alex said: Different brands/types of tires that are nominally the same specified size, can sometimes be slightly different. You changed brand and if the old tire was a little close before, the new tire may be just slightly taller. Add this to a new chain that has not loosened up at all yet and you get the rubbing. Don't be so quick to blame the mechanic. Besides....you are installing a non stock tire size and larger than stock sprocket size so clearance issues are definitely something that you risk.

- Did you buy the parts through them or did you buy the stuff on line and bring it to them to install?
- Did you research whether or not this combo would work before you decided on it?
- Did you look at Shinko's and Bridgestone's data on their tires to see if there was any difference in the diameter of each tire?

If you simply had a mechanic install a NON STOCK tire, chain, and sprocket on your bike, at your request, without doing your own due diligence to make sure it would work, then why would the mechanic and the shop he works for suddenly be crap and deserving of getting bashed on the internet?

I probably should have clarified. I bought the Shinko 140/60-17 tire AFTER the mechanic installed my BT45 and showed me it doesn't fit.
The BT45, RK chain & sprockets were a combo I went with the last time I needed to replace my those specific parts, too, and it doesn't my make sense that they fit last time but don't this time.
So again, I had the BT45 140/70-17, took it to Langston Motorsports to have it installed together with my RK chain & 15/45 sprockets, but the guy showed me it was going to be a problem after the installation. I had my bike towed home through AAA to avoid crashing on the ride home. I then ordered a Shinko tire and had them install that.

[Lil_Green_Demon]

Originally Posted by bruce71198

Picture?

The BT45 tire is already off, so I can't provide pics unless you feel like seeing the Shinko tire on a 250R instead. Even then, it's nothing special, so I don't think I'll be taking a pic.

[rojoracing53]

Originally Posted by Lil_Green_Demon

The BT45 tire is already off, so I can't provide pics unless you feel like seeing the Shinko tire on a 250R instead. Even then, it's nothing special, so I don't think I'll be taking a pic.

Simple solution is to go two smaller on the rear sprocket and enjoy a less buzzy ride.

[Lil_Green_Demon]

@rojoracing53 So just for future reference, should I just go with a 14/43 set up?

[rojoracing53]

Originally Posted by Lil_Green_Demon

@rojoracing53 So just for future reference, should I just go with a 14/43 set up?

Personally most of my riding is done at 60+ mph with almost no city riding so I run a 15-41. No I don't even notice the taller gearing in the canyons or taking off from a stop light it just works everywhere good and on the hwy its great. If you want to go back to the 14 then I'd go 42t or 41t if you want to feel what you have with the 15-45.

Some people say they don't like the taller gearing because it makes the bike feel slow, news flash its a 250 the thing is slow ether way so it doesn't really matter

Just a quick reference to keep in mind 3 teeth in the rear is equal to 1 in the front.