I bought a sprocket/chain replacement kit as a genuine part from Triumph at BikeBiz Granville for $288.04. This was considerably cheaper than buying individual non-genuine parts of the same quality. The kit includes:
- 16T front sprocket
- 50T rear sprocket
- 122 link RK525X-Ring chain
- New lock washer for front sprocket.
Tool list:
- 36mm socket - for front sprocket removal
- large flat blade screw driver
- hammer and flat piece of 1/8" metal about 30mm long and 25mm wide - to open/close lock washer
- 8mm socket and 8mm ring spanner - to remove front sprocket cover and gear lever
- 27mm socket - for rear axle nut
- 13mm and 12mm open end spanners - for chain adjuster bolt/nut
- 3mm and 5mm Allen keys - for removal of chain guard
- Chain tool.
Some of these tools are shown here:
1. Put the bike on the centre stand.
2. Remove front sprocket cover - 2 x 8mm bolts after removing the gear change rod bolt and leaning it to one side.
3. Lever up the lock washer side securing the sprocket nut with the flat blade screw driver.
4. If you are doing this job by yourself, sit on the bike and fit the 36mm socket to the front sprocket nut in your left hand. Put your foot on the rear brake and loosen the sprocket nut - this way the chain takes the strain rather than putting it in gear and straining the gearbox.
5. Leaving the loosened nut and front sprocket in place, get your chain tool out and break the chain at the rear sprocket and remove the chain. Roll it out around the front sprocket and pull it out the back. Remove the chain guard. Remove the front sprocket and lock washer.
The wear in the chain compared to the new one is evident in the sideways play - see below. By the way, if you don't have a good quality chain tool for a 525 chain, its worth the money to buy one - about $100. I've had one for years and used it on many bikes.
6. Undo the 32mm rear axle nut and remove the rear axle and wheel.
7. Lay the wheel disc-side down on a towel. Remove the 6 x 14mm nuts holding the rear sprocket in place. Clean up the rim/wheel/hub/nuts etc and put the new sprocket on and tighten the 6 nuts back up. I always do them up across diagonals - eg. do all nuts up to finger tight, then tighten nuts in the following order - 1, 4, 5, 2, 3, and 6. This ensures no warping of the sprocket. There wasn't a lot of wear on the old sprocket surprisingly but it was differently shaped - see below.
8. Fit the rear wheel back onto the bike - you'll need to loosen the chain adjusters as the old chain would have stretched quite a bit. For reference, my new chain adjustment with the new chain/sprockets in place had 6 dots showing on the chain adjusters.
9. Roll the new chain around both sprockets and sit the two ends next to each other on the top of the rear sprocket. Insert the new chain link joiner after inserting 2 of the included rubber O-rings onto the link. After inserting, fit 2 more O-rings and the flat plate finger tight. Use your chain tool to press the plate onto the chain compressing the rubber O-rings and allowing about 1mm of the chain link studs to show through the plate. Change fittings on the chain tool and then splay the ends of the chain link studs to keep the plate in place. Don't go overboard splaying the ends though, otherwise the link might become stiff - if you are using a good chain tool, it won't let you over splay the link.
10. Sit back on the bike and put on the rear brake while you tighten the front sprocket nut. Then use a flat bit of metal and a very gentle tap of the hammer to bend the lock washer over on side of the nut. There is probably a genuine Triumph tool to do this but this works ok.
11. Adjust chain to factory spec - 30mm slack.
12. Reassemble front sprocket cover, gear linkage and chain guard - done.
2. Remove front sprocket cover - 2 x 8mm bolts after removing the gear change rod bolt and leaning it to one side.
3. Lever up the lock washer side securing the sprocket nut with the flat blade screw driver.
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| You can see the lock washer secures the nut by being bent over it. Its fairly soft and easily bent off the nut though. |
4. If you are doing this job by yourself, sit on the bike and fit the 36mm socket to the front sprocket nut in your left hand. Put your foot on the rear brake and loosen the sprocket nut - this way the chain takes the strain rather than putting it in gear and straining the gearbox.
5. Leaving the loosened nut and front sprocket in place, get your chain tool out and break the chain at the rear sprocket and remove the chain. Roll it out around the front sprocket and pull it out the back. Remove the chain guard. Remove the front sprocket and lock washer.
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| The gap between the teeth was significantly worn compared to the new front sprocket teeth gaps. |
The wear in the chain compared to the new one is evident in the sideways play - see below. By the way, if you don't have a good quality chain tool for a 525 chain, its worth the money to buy one - about $100. I've had one for years and used it on many bikes.
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| New chain (bottom) has way less sideways movement compared to the old one (top). |
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| Chain tool - breaks and makes chains from 420 to 530 size. |
6. Undo the 32mm rear axle nut and remove the rear axle and wheel.
7. Lay the wheel disc-side down on a towel. Remove the 6 x 14mm nuts holding the rear sprocket in place. Clean up the rim/wheel/hub/nuts etc and put the new sprocket on and tighten the 6 nuts back up. I always do them up across diagonals - eg. do all nuts up to finger tight, then tighten nuts in the following order - 1, 4, 5, 2, 3, and 6. This ensures no warping of the sprocket. There wasn't a lot of wear on the old sprocket surprisingly but it was differently shaped - see below.
8. Fit the rear wheel back onto the bike - you'll need to loosen the chain adjusters as the old chain would have stretched quite a bit. For reference, my new chain adjustment with the new chain/sprockets in place had 6 dots showing on the chain adjusters.
9. Roll the new chain around both sprockets and sit the two ends next to each other on the top of the rear sprocket. Insert the new chain link joiner after inserting 2 of the included rubber O-rings onto the link. After inserting, fit 2 more O-rings and the flat plate finger tight. Use your chain tool to press the plate onto the chain compressing the rubber O-rings and allowing about 1mm of the chain link studs to show through the plate. Change fittings on the chain tool and then splay the ends of the chain link studs to keep the plate in place. Don't go overboard splaying the ends though, otherwise the link might become stiff - if you are using a good chain tool, it won't let you over splay the link.
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| Splayed chain link stud ends. |
11. Adjust chain to factory spec - 30mm slack.
12. Reassemble front sprocket cover, gear linkage and chain guard - done.
