maintenance question

souter

Hi,
I recently got a new back wheel fitted on my bike. I then found that it wouldn't shift into top gear (and I'd been pootling about in 2nd thinking I'd grown extra muscles).
The problem would appear to be that top gear sprocket is too close to the frame. The bike is a venerable hybrid touring yoke, 18 gears with quick release axles.
Is there any way to adjust the axle so that the sprockets (forgive my terminology) are further from the left side of the frame?
I had a look but the axle seemed fairly integral with wheel, the only access I could see were a couple diametrically opposed pits in the front of the sprocket which I seem to remember shifting with a hammer and brad many years ago but I also have a recollection of a cascade of ballbearings and springs which I am reluctant to repeat.
Any suggestions? I'll clarify my woefully imprecise description if neccessary.

Ta.

Morgan

It sounds more like the rear derailleur needs to be adjusted, specifically the limit screws.
http://www.parktool.com/repair/readhowto.asp?id=64

Itsfixed

I agree. Derailleur needs to be adjusted. The mechanic should do this for you if you can't figure it out yourself. I've done this myself before with varying degrees of success, but I wish I'd seen the link Morgan posted - very helpful.

souter

Good link, but the problems not the derailleurs - that was my initial diagnosis but I let the cable out, pulled the gears out manually etc but still won't engage top gear because the frame gets in the way.


If a bad ascii pic is any good:

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       |x|||
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the chain wants to go in x, but there's no room

daymobrew

souter wrote:

Good link, but the problems not the derailleurs - that was my initial diagnosis but I let the cable out, pulled the gears out manually etc but still won't engage top gear because the frame gets in the way.

Have you loosened the limit screw? It determines how far the derailleur will go toward 'x' gear, even if the cable is let out completely. Can you see that this screw is not hitting against the bit that it attached to the derailleur i.e. the limit screw is not preventing it from moving to gear 'x'.
Chains are quite narrow and only need a few mm either side of the sprocket to fit.
If you can take some photos that would be great.
You may need to go back to the bike shop.

BeardyGit

What's the bike/frame, and what's the rear hub/cassette combo?

Is it a cheap assed, badly adjusted POS wheel or a reputable brand/builder?

Is the lowest (smallest) ring larger than on the old cassette?

souter

Hi,
The bike is a Claude Butler hybrid, 15 yrs old, but still class. The wheel was from City Cycles in Fairview which I've generally found to be pretty good. It was cheap - I was in a rush and they didn't have the good wheels in stock.
The problem has nothing to do with the gears, and is entirely to do with the wheel - if you imagine the smallest sprocket hard against frame. The back wheel lug is flat in the vertical, but just above the frame becomes tubular and starts to slope to meet the seat pillar (standard bike frame). The clearance between the teeth of the sprocket and the bulge of the frame is not adequate to allow the chain on top. I've attached a picture, not very clear, but the problem is the wheel, the question is can it be adjusted?

kona

funnily it looks like your cones that hold your bearings in the hub arnt there??? did you fit the freewheel or did city cycles??
are you running a 7spd chain???or a 6speed??,
your bike needs a clean too:)
just re-read the thread you say 18 speed?? pic says 21speed, they put on the wrong freewheel...go back and shout and scream at their incompetence!!and bring it to a proper bike shop next a shop that doesnt stock shimano deore isnt worth a **** tbh.
i was looking for new bars for my jump bike, the guy in that shop was showing me the cheap crap taken from cheap bikes,i like my face the way it is so i think cowboy is the name im after.

souter

Thanks Kona, funny how I never noticed the 6 cogs had gone to 7, which would explain a lot.
City cycles did the fitting, I'll go and make a fuss.

And yes, it needs a clean - but I'm scared what I'll find under the mud.

John