I hate writing lists but I suspect that I will be writing a few with this build.
Firstly I need to take 2 mm from the bottom of each rear drop out. This is due to the spindles on the rear wheels being 10 mm in diameter and the drop out slots being a bit different!
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| Rear drop out |
This link explains the history of Raleigh.
When this is done I can mount the rear wheel and work out the chainline.
The chainline needs to be straight otherwise there is a risk the rear cog and the main crank will wear in such a way that the chain will come off.
I have put the rear wheel on roughly where I think it will go and measured the rear chainline at 44 mm. Now I need to transfer that to the crank by measuring 44 mm from the center of the seat tube to the center of the crank. The main stumbling block for this is I don't yet have a crank.....or a bottom bracket...YET! The length of the axle in the bottom bracket together with the design of the crank will influence the front chainline as the diagram on the left illustrates.
Sheldon has more info on the early Raleigh issues.
Just wish I knew about it before I'd started!
As for the bottom bracket, when I have mounted the rear wheel correctly I can accuratly measure the rear chainline, I have my eye on a Sturmy Archer 44 teeth crank on E-bay which the manufacturer states has a 45 mm chainline on a 110 mm spindle. All 'English thread' bottom brackets these days are for a 68 mm shell. Of course it would be too much to ask for this frame to have any thin standard on it!! My shell is 71 mm ish. This is due to the fact it used to use an old style cup and cone arrangement which was nice.
So the choice is I can either spend ages looking for the right size cups, the correct length spindle together with the right bearings or...........I just say bugger that and buy a threadless bottom bracket (BB)! Which is what I'm going to do. A threadless BB does what the name suggests, It doesn't use the threads in the BB shell. Instead it tightens up against the outside of the shell and uses a tapered shim inside to stop it all from working loose. A lot less mucking about.
Due to the fact that the specification of the crank suggests a 45 mm chainline for a standard 68 mm BB with a 110 mm spindle (Oh do try and keep up!) My BB shell is 3 mm wider so I need to take that into account. So if I had a 110 mm spindle my chainline would actually be 48 mm which is wider than that on the rear. I could have problems with wear on the crank and the chain coming off when I'm trying to pose whilst cruising around! Not good. So looking at the options for the threadless BB, they do it in a 107 mm version. Which is only bloody perfect!
These measurements will only ring true when I have fitted the rear wheel.
So to work then. Where did I put that angle grinder!
The chainline needs to be straight otherwise there is a risk the rear cog and the main crank will wear in such a way that the chain will come off.
I have put the rear wheel on roughly where I think it will go and measured the rear chainline at 44 mm. Now I need to transfer that to the crank by measuring 44 mm from the center of the seat tube to the center of the crank. The main stumbling block for this is I don't yet have a crank.....or a bottom bracket...YET! The length of the axle in the bottom bracket together with the design of the crank will influence the front chainline as the diagram on the left illustrates.
Sheldon has more info on the early Raleigh issues.
Just wish I knew about it before I'd started!
As for the bottom bracket, when I have mounted the rear wheel correctly I can accuratly measure the rear chainline, I have my eye on a Sturmy Archer 44 teeth crank on E-bay which the manufacturer states has a 45 mm chainline on a 110 mm spindle. All 'English thread' bottom brackets these days are for a 68 mm shell. Of course it would be too much to ask for this frame to have any thin standard on it!! My shell is 71 mm ish. This is due to the fact it used to use an old style cup and cone arrangement which was nice.
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| Bottom bracket shell |
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| Cup and Cone |
So the choice is I can either spend ages looking for the right size cups, the correct length spindle together with the right bearings or...........I just say bugger that and buy a threadless bottom bracket (BB)! Which is what I'm going to do. A threadless BB does what the name suggests, It doesn't use the threads in the BB shell. Instead it tightens up against the outside of the shell and uses a tapered shim inside to stop it all from working loose. A lot less mucking about.
Due to the fact that the specification of the crank suggests a 45 mm chainline for a standard 68 mm BB with a 110 mm spindle (Oh do try and keep up!) My BB shell is 3 mm wider so I need to take that into account. So if I had a 110 mm spindle my chainline would actually be 48 mm which is wider than that on the rear. I could have problems with wear on the crank and the chain coming off when I'm trying to pose whilst cruising around! Not good. So looking at the options for the threadless BB, they do it in a 107 mm version. Which is only bloody perfect!
These measurements will only ring true when I have fitted the rear wheel.
So to work then. Where did I put that angle grinder!
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