Bonneville America Forums Forums Technical Forums General Tech chain and sprockets life?

I was just wondering How long are the chain and sprockets lasting. I have 16000 on mine and they are in great shape. I know a lot depends on how you ride, but to those who have changed them out, how many miles did you get?

I've done mine twice and both sets lasted around 17,000 miles.

I have a little over 22,000, the chain has stretched evenly, but there isn't any adjustment left. Rear sprocket appears OK, but am replacing it. I have a little over 5K on the Dunlop 404, it's down to the wear bars. Bummer, I thought it would last longer.

JH

is it wrong that I haven't even had to make a chain adjustment in the first 8000 miles? i tested it a few hundred miles ago per the haynes manual and it was within the spec, although i had to approximate the (i think it was) 20 lb weight that was supposed to be applied.

on that note, what do y'all use as a weight to accurately measure this??

Chains and sprockets are the same as tires, brakes, and gas mileage. Your results may vary.
I changed mine out at about 15000 miles, because I had the new ones, I was changing other related parts, and the front sprocket was showing some wear. I still had plenty of adjustment left on the chain however. I probably could have got another 5k out of them easy...

Quote:

---

is it wrong that I haven't even had to make a chain adjustment in the first 8000 miles?

---

The current chain kit I have didn't need adjustment till, well, till I took off the rear wheel for a new tire. Right around the 7000 mile mark.

If you're concerned with the lifespan of the chain & sprockets, I've had a new set of sprockets made a little wider than standard and used a 530 chain instead of a 525 chain. I'm told it'll significantly increase it's usable lifespan.

Matt

Changed out last month at 24k+, about 2 years. The chain was getting tight in one section (the o-rings were pretty much gone), but it had not 'stretched' (still don't get that steel 'stretches', wears out maybe). Couldn't get it to adjust with any consistency. The sprockets were good, but wanted to change it all as a set for no good reason.

Just a heads-up, I ordered a stock replacement chain and sprocket kit, and got the pre-06 Speedmaster set with the 16t. Apparently there's only one part number so I don't know how you order a BA (17t) or post 05 SM (18t) set.

JJ, do the new SMs come with 18/42 sprockets? If they do, you would think a factory chain/sprocket kit would be available. It would be great if I could order the complete set with the set up I've got. I'm surprised they would jump from the 16T to an 18T - big difference. It would make a SM not as quick off the line as a TA stock, even with the additional low end torque. I assume they both still have the 42T rear sprocket.

I have around 18,500 on mine, but it doesn't have much adjustment left, and I have been pretty good about lubing every 500-600 miles. I will probably need to replace it this fall. I am going with a 18 tooth sprocket.

To you guys that are changing out chains because you run out of adjustment, you might want to take off one or two more links the next time you install a new one. That's what the BMW tech instructor, who has a small shop on the side, did on mine last December.

PES: I just installed Brents 18 Tooth about a month ago and there's No looking back ! I love it!!

There is only one part number for a chain and sprocket kit, A9618019.
This part is listed for Americas and Speedmasters all years, including the 06 Speedmaster.
But up to 05 SMs come with the 16, all Americas have the 17, and the 06 SM comes with an 18 on the front so I don't know how they tell the difference.
Looking on the Triumph web site for accessories, select America, click on any year and category 'other', you'll find the part number for the c&s kit titled 'Chain and Sprocket Kit Speedmaster'.

If I knew how to send an email to Triumph UK and ask about it, I would. I suspect there's a mistake somewhere and the America part number got lost in the shuffle. The 06 SM has to have its own part number, maybe one of the UK members can get a tech support email address from the headshed and get it.

Stupid newbie question... what does going from the stock sprocket to the 18 do?

JJ, please keep on top of it. Obviously it they are selling the units with 42/18, they will come up with a part number for a chain kit that includes those spockets. Evem though I have a TA, the SM kit that uses what I have and need to replace would be the ticket.

Don - the 18 tooth gives you lower revs at cruising speed - you lose a bit of low end power but much better on the highway...

Al,
I went 28,000 miles with a few adjustments. Replaced front sprocket and chain. At 44,000 I need all three badly.
I'd suggest replacing all 3 at 20,000 miles or get a belt drive, then ride 100,000 miles. I want one, but am squeaking every mile out of my second chain. I may not make it, but still trying - I will have a belt soon.

I doubt that the average lifespan of a belt is 100,000 miles. I read one poll where over 50% of the replies were along the lines of belts needing replacing around 35-50,000 miles. And while chain and sprockets do require more maintenance and replacing, pulleys and belts are subject to wear also.

If you do your own maintenace, belt drives can be cost effective, but from what I hear dealers charge an arm and a leg for the job(from one Harley board; "The stealer wants $210 for the belt and 4 hours @ $90. Plus $100 for the tow.").

its a lot more work to change a belt on a harley then the belt on our bikes with the kit

Frank

Thanks Loco! Since most of my riding is Highway... it sounds like that is my next mod.

Thanks to RamSound and the TriumpheStore link for the chain part numbers.

The elusive BA sprocket kit part number:

BA with the 17t: A9618015

Speedmaster with the 16t: A9618019

Don't know why the parts fiche lists the -19 for both!