Jackshaft cassette wear and single cog replacement for shifter bike

sactownie

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Got my new motor a month ago and have put some serious miles on it in that time.
Took a 23 mile ride over the weekend and near the end my main chain started jumping teeth from the worn chain.
It started doing it in 8th gear (8 speed cassette) then started doing it also in gears 5-on down so I had to go slow in 4th gear to make my destination.
I replaced the chain and it works perfect except for 8th gear. It was still jumping teeth. I took the cassette off and ground out the "hook" especially on the last tiny 11 tooth cog but it still does it sometimes in that gear.

My question, is it possible to find a 11 tooth cog for shimano cassette anywhere or should I just pay the $20 for the full replacement?
I'm thinking that only motor bikers wear out that last gear so shimano probably doesn't bother with a replacement for it?
 
lol I ALLREADY TRIED LOCAL BIKE SHOP. they dont sale single cogs anymore since the 80s, they said everything made in china now china cheap, you buy whole cogs now!
I guess im screwed i have to buy the whole thing the little 11 tooth cog is going to wear out every 500 miles
 
No one sells individual sprockets for cassettes. You have to purchase a complete replacement cassette just to get the precious 11 tooth, 12 tooth, 13 tooth sprockets.

Generally the chain will start jumping teeth on the smaller cassette sprockets when chain wear reaches 80% or greater.
 
yea this sucks. 11 tooth cog isnt going to last very long under 2 stroke power. so is everyone else with a shifter bike having the same problem???? I put maybe 200 miles on mine before is started skipping gears in 8th gear!
 
I use 9 speed chain (because my application has a specific requirement to use the narrower 9 speed chain width) and typically get 1,000 kilometers (600 miles) out of the right hand side drive chains and rear cassette when they measure in at 100% stretch, upon which i replace the right hand side chains and rear cassette with brand new items.

I usually get around 3,000 kilometers (1,900 miles) out of the right hand side 9 tooth and 36 tooth and 48 tooth jackshaft sprockets, and get around 6,000 kilometers (3,700miles) out of the left hand side jackshaft and engine sprockets.

I tend to haul a lot of weight towing bicycle trailers on unpaved tracks and bicycle trails, which adds significantly more chain and sprocket wear than the average person will experience.
 
I guess I should have replaced the chain when i put the motor on it. I got the bike 2nd hand so who knows how the original owner rode/maintained it.
 
I use 9 speed chain (because my application has a specific requirement to use the narrower 9 speed chain width) and typically get 1,000 kilometers (600 miles) out of the right hand side drive chains and rear cassette when they measure in at 100% stretch, upon which i replace the right hand side chains and rear cassette with brand new items.

I usually get around 3,000 kilometers (1,900 miles) out of the right hand side 9 tooth and 36 tooth and 48 tooth jackshaft sprockets, and get around 6,000 kilometers (3,700miles) out of the left hand side jackshaft and engine sprockets.

I tend to haul a lot of weight towing bicycle trailers on unpaved tracks and bicycle trails, which adds significantly more chain and sprocket wear than the average person will experience.

The weight you pull is probably about = to what I weigh so I guess 600 miles per chain is about right what I got out of mine before it started jumping teeth. bike had very low miles on it when i got it but it was 13 years old.
New problem i have now is the rear wheel has broken 4 spokes in 2 weeks.
I have a decent wheel that the bike came with but it seems to be failing now trying to pull my weight and the torque of the motor is just to much i guess.
Should I buy a different wheel or have the LBS rebuild mine for $100+?
 
I hear of people breaking spokes, but in 50,000 kilometers of riding (30,000 miles) the only time that i've broken spokes was is in the very early days, when the bike was suffering from repetitive chain suck issues; ripping out the rear derailleur, then sending it into the rear wheel; tearing out spokes in the process, actually, tearing up everything in the process; including the front derailleur as well.

In every other mode of operation (over the last 49,000 kilometers), i have """never""" broken a spoke through torque or weight related issues, and i've been known to haul heavy loads.

Interestingly, the original wheels were 'Quando', typically found on lower end mountain bikes, but the rear wheel and hub lasted just shy of the 50,000 kilometer mark, with the hardening wearing away on the internal axle bearing area.
That particular wheel has been replaced with a lower end Shimano item (because it was a cheap buy at $50) and it is the very wheel you can see in the photos of my Heavy Haul thread.
I can report that it has not broken a spoke.
 
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Also make sure you keep them lubed! I had chain jumping and wear issues before I regularly lubricated everything.
 
I was using dry type lubes on the chains. Since this happen I have gone to more conventional oil type messy lube. I couldn't see how the dry type was lubricating the cassette gears.
I have found this 10 pack of 11 tooth cogs for 9 speed cassette on ebay. http://www.ebay.com/itm/NEW-Set-of-...Cassettes_Freewheels_Cogs&hash=item1c295b6846
Does anyone see any reason this wouldn't work on an 8 speed cassette? They come out to about $1.60 a cog which isn't bad if you even had to replace it every 300 miles.

As for my broken spokes, I believe I missed an important step when i replaced that 1st spoke. I didnt know you had to release tension on the surrounding spokes. Im going to try to sort that out today. haven't rode in a few days, needed a break from it LOL.
If this dont work ill just purchase a 36 spoke wheel off ebay for $50 delivered and see how far that gets me.

Oh and by the way I want to run a way bigger tire on the rear to cushion the bumps in the road, I was looking at the cst cyclops in a 26x2.4 size. I have chainstay clearance but looks like my jackshaft gear to engine output sprocket is going to interfere! what to do with that? put some spacers on it to shift the sprocket more to the left?
 
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