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hi I am struggling to get first gear on my Raleigh Equipe Eroica Bike.
In last years event I couldn’t get it to shift into and hold 1st gear so I have replaced the cassette and chain (and the wheel as it was badly buckled) but it still won’t move far enough across. The Stop screw is wound right out but the mech is bottoming out on it own body.
A bit of manual flexing the mech will get the chain on to the first sprocket. Before I bend the hanger am I missing something like a spacer that stops the cassette screwing fully on to the freewheel?
thanks for any help
I would be reaching for a hanger alignment tool.
Yes, check gear hanger alignment first - the rear wheel QR axle stub screwed into the hanger can be used as a makeshift hanger alignment tool.
The pivots in your rear mech make be worn / sloppy too.
Having the wrong chain line might also do this. Measure from the centre of the bike to the middle of the chainrings to establish what it is, then find out (somewhere - Sheldon Browne maybe) what the chain line should be. If it is wrong then you'll have to adjust by changing the bottom bracket axle length.
And to find out what it should be you'll probably need to measure the rear dropout distance. It may not be 130 or 135 - might be 126 or less.
Most crank sets specify a bottom bracket axle length, and you'll get gear change problems if the wrong length is used.
Chain line relevant to rear gears? For the laugh that gave me I'll overlook use of "eroica" 😀
OP try filing the stop? Or new rear mech, or spacing the freewheel out with a spacer (you also mention a cassette tho)
If it the gear looks vertical then it is vertical btw.
yes al it is. If the chainring is too far inboard it will increase the distance the mech has to travel to get to the smallest cog as the angle of the chain becomes more acute.
Indexed or friction mode on the shifters? By first gear do you mean biggest cog on the back or smallest?
I found on my six speed bike that it wouldnt stay on the biggest cog on the back when I was in friction mode on the shifters but in indexed it would.
Back in the day I had a 6-speed freewheel and I don't recall them needing a spacer on the freewheel thread
There were two types, the ultra-six that was the same width as a standard 5-speed, and a standard 6 that needed the axle and frame widening by 6mm. If you have an older mech with the standard 6 then you might run out of adjustment
History linky Scroll down to "How many speeds?"
If it's a cassette then I'll bow out now coz I didn't have one of those back then
Could also be that the hubs been respaced badly. Had this when moving axle spacers around to allow space for 6 and 7 speed freewheels.
How far is the small sprocket from the drop out?
Unless you've got a 200mm long bottom bracket axle, chain line is irrelevant.
tjagain
Thank you.
ghostlymachine
Chain line will effect shifting at the back. If you don't believe me put a boost crank on a non boost bike and see if you can get the chain to stay on the biggest cog at the back. You need different chain lines for different frame set ups.
Chainline on a road bike makes no difference at all, unless you do something stupid.
Anything between 40 and probably not far off 50mm will work. Biggest issue i've found is the chain rubbing against the inside of the large ring in the chainline is too small, and/or picking up on the shift pins (probably not an issue on a bike of this age.)
This doesn't sound like an issue relating to chainline anyway. More like the range of the mech parallelogram compared to width/location of the freewheel.
thanks all for your thoughts.
Friction shifters. Sorry you have lost me on chain line. Chain rings are original and it worked when i first got it, Mech hanger looks vertical.
I think it is time for LBS to have a look
Thanks again
As above chain line not relevant.
Freewheel spacer is your friend - I assume you are using the original mech which doesn't have enough travel.