marioweldinginc

2003 400ex chain drive too short

31 posts in this topic

Got all my pieces for Christmas and installed the new drive sprocket (13T) new driven sprocket (38T) and a new 520 xtg chain. Made the chain same size as factory chain and it was too long. It would touch the skid plate. I removed another link and side plates. Now the chain is half a link too short. I cannot get enough adjustment on the slack adjuster. To topf it off on one end i broke a roller so that link has to come out too. Would i be able to add a half link and maybe rivet the repair in?? I know DID has a rivet link but i cant find one for sunstar.

I repair non oring chains (#40 - #120) alot on industrial equipment so im familiar with half links and adding aditional links with cotter pin style links and master links. But thats low speed 200 - 300 rpm and high torque.

520 chain seems to be voodoo magic to me.

What should I do at this point?? Help im dying to try this sprocket combo..

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go ahead and get ya a half link ... the 1's with the pinan cotter pins will work just fine ... but keep a spair just incase ... and after a couple rides it should be stretched enough to take out the half link ... i have had to do it b4 in a few of mine ... i have a polaris 350L that i have 10 different sprockets for that i drag race and have a few chains and use the half links with no problems ..

the polaris 350L has a snowmobile 600 tripple motor on it .. an havent broke a half link on it yet so far...

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That was my next question. Use the half link till it stretches enough. Got it

Now where can i get two links? Think the dealer might have a couple laying around?

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lol...dont know about all that shit ...but if ya want you can send me some good riding pics of your riding trips.. ill add them 2 my collection .. i have 8 thumb drives full of riding pics from all over the us an a couple other countrys

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Ill write a full report on the new combo. There are a couple of youtube videos of Mark and I. He is using the gopro on his helmet but everyonce in a while you see me staying with him even in the worst of the mud.

Its Markdgb channel on youtube.

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ill have 2 look thoes up on youtube an check it out .. but if ya can email me some riding pics it would be cool ...

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Wow sorry to here about your chain !! I can go from 12t to a 14t with the same chain just by adjusting it at the axle :yes:

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I couldnt with the new chain. With the old chain i could but i ground out the rivets on the old chain

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Edited by marioweldinginc

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maybe I dont have enough adjustment in the axle?? It was very hard to turn. should i disassemble the rear?

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Got all my pieces for Christmas and installed the new drive sprocket (13T) new driven sprocket (38T) and a new 520 xtg chain. Made the chain same size as factory chain and it was too long. It would touch the skid plate. I removed another link and side plates. Now the chain is half a link too short. I cannot get enough adjustment on the slack adjuster. To topf it off on one end i broke a roller so that link has to come out too. Would i be able to add a half link and maybe rivet the repair in?? I know DID has a rivet link but i cant find one for sunstar.

I repair non oring chains (#40 - #120) alot on industrial equipment so im familiar with half links and adding aditional links with cotter pin style links and master links. But thats low speed 200 - 300 rpm and high torque.

520 chain seems to be voodoo magic to me.

What should I do at this point?? Help im dying to try this sprocket combo..

Sent from my SGH-T959V using Tapatalk

Sent from my SGH-T959V using Tapatalk

odds are you are not too short at all, i see this alot. im willing to bet that either the sprockets are not completely aligned, or when you put the chain back on you tightened one side of the axle bolt one or 2 turns more than the other side. it might look straight to the eye but each side must have the exact same revolutions to the mm

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maybe I dont have enough adjustment in the axle?? It was very hard to turn. should i disassemble the rear?

NO! dont disassemble anything bc your going to turn an easy job into a problem. its supposed to be hard to turn, it wont just unlock and loosen. try the alignment

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The front sprocket mounts the same way as the factory. With the 2 bolts and clip. It even has the same raised edge. The rear sprocket is a factory honda 38t. I didnt loosen anything besides the 4 pinch bolts. I only changed the rear sprocket and never touched the rear hub or axle.

I will double check everything tomorrow. Thanks for all your help guys

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odds are you are not too short at all, i see this alot. im willing to bet that either the sprockets are not completely aligned, or when you put the chain back on you tightened one side of the axle bolt one or 2 turns more than the other side. it might look straight to the eye but each side must have the exact same revolutions to the mm

Rereading your answer, i am not sure exactly what you mean by axle bolt. You mean the lock nuts on the right side by the brake caliper? Or the pinch bolts or the hub that the rear sprocket fastens to?

Also would a laser work to check alignment. I use them when i set up jigs.

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yes a laser is exactly how you do it,

-set the laser on something so it is centered on the rear sprocket (its more accurate than going from the top or bottom)

-off the top of my head i want to say the pinch bolts. there should be 2 with room for the nuts to be adjusted either way. they have to be the exactly the same or it can throw your sprocket/chain/ rear end alignment off

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yes a laser is exactly how you do it,

-set the laser on something so it is centered on the rear sprocket (its more accurate than going from the top or bottom)

-off the top of my head i want to say the pinch bolts. there should be 2 with room for the nuts to be adjusted either way. they have to be the exactly the same or it can throw your sprocket/chain/ rear end alignment off

On the swingarm? There are 4. I have a stock swingarm. im on my cell so i cant u/l an exploded view of a parts diagram. Anyone have one handy??

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Edited by marioweldinginc

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Update. Threw the sunstar chain to the side and bought a DID chain. I broke the links to proper length and installed in about 10 min including adjustment. This isnt a bashing on Sunstars asbthe sprockets are top notch part but i feel that the DID chain seems better made. The DID cost thirty dollars more from the stealer.

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Update. Threw the sunstar chain to the side and bought a DID chain. I broke the links to proper length and installed in about 10 min including adjustment. This isnt a bashing on Sunstars asbthe sprockets are top notch part but i feel that the DID chain seems better made. The DID cost thirty dollars more from the stealer.

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OUCH Mario !! If it gets you riding then all good !!:yes:

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I can pull a house with the 13T front. 1st gear is so short but I can almost idle in 1st without stalling. Waiting for some $$$ then its 22"x11x9 GBC Gator tires. That should gimme some more 1st gear

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Got all my pieces for Christmas and installed the new drive sprocket (13T) new driven sprocket (38T) and a new 520 xtg chain. Made the chain same size as factory chain and it was too long. It would touch the skid plate. I removed another link and side plates. Now the chain is half a link too short. I cannot get enough adjustment on the slack adjuster. To topf it off on one end i broke a roller so that link has to come out too. Would i be able to add a half link and maybe rivet the repair in?? I know DID has a rivet link but i cant find one for sunstar.

I repair non oring chains (#40 - #120) alot on industrial equipment so im familiar with half links and adding aditional links with cotter pin style links and master links. But thats low speed 200 - 300 rpm and high torque.

520 chain seems to be voodoo magic to me.

What should I do at this point?? Help im dying to try this sprocket combo..

Sent from my SGH-T959V using Tapatalk

Sent from my SGH-T959V using Tapatalk

did you losein the four bolts on your swing arm and roletate your axle forward ajust your slack while your sitting on the bike if you dont the chain will be to tight when you mount your bike resulting in streaching your chain and sproket wear before its time.

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i agree with opewhitaker. by doing what was stated above will also do a proper chain slack adjustment for the top and bottom. i would put the link back in and try this first.

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I went by the shop manual instructions. I adjusted without a rider on the machine. Drove it for about a couple of miles (im just outside NYC not alot of dirt around) then readjusted the chain again.

As I stated above, I went with the DID chain and sized,installed and adjusted in about 10-15min. I am going to use the Sunstar chain as a spare if needed as I have a few extra links now.

This thread is now closed

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lol... ooooops i just reopened it ...lol... Y not just go buy a shaft drive sport quad an eliminate the whole problem with worn chains and sprockets ...lol...

SORRY I JUST COULDENT HELP MYSELF ,,,,,,....LOL

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lol... ooooops i just reopened it ...lol... Y not just go buy a shaft drive sport quad an eliminate the whole problem with worn chains and sprockets ...lol...

SORRY I JUST COULDENT HELP MYSELF ,,,,,,....LOL

:aargh::aargh::aargh::aargh::aargh::aargh::aargh::aargh::aargh::aargh::aargh::aargh::aargh::aargh::aargh::aargh::aargh::aargh::aargh::aargh::aargh::aargh::aargh::aargh::aargh::aargh:

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hahaha thats just 2 funny ...lol.. my sport quad never needs new chain or sprockets an it has never needed the rear brakes chainged ... its far superior to that old 400ex...lol... an it will woop it any time on a drag race or in the mud... or up or down hill ...lol....

another fine post dug up by THE POST MINER ! ! ! .....HAHAHA

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