Technical question

[Martini-night]

Hello, I've got a couple of summer projects,several retro frames to build.
Regarding the rear wheel building/lacing with 7 speed cassete ; does the picture apply to the frames with wider and lower space between the dropouts??
-I've got 2 frames, a 122mm and a 127mm spaced frames and i was about to start lacing/ building the rear wheels(1991 shimano Exage hubs),but I'm quite confused how should i lace.
- All my retro complete bikes here are the same on the right picture.
just wondering about the smaller 124mm frame I've got...

 

[Ippikin]

Hello, I've got a couple of summer projects,several retro frames to build.
Regarding the rear wheel building/lacing with 7 speed cassete ; does the picture apply to the frames with wider and lower space between the dropouts??
-I've got 2 frames, a 122mm and a 127mm spaced frames and i was about to start lacing/ building the rear wheels(1991 shimano Exage hubs),but I'm quite confused how should i lace.
- All my retro complete bikes here are the same on the right picture.
just wondering about the smaller 124mm frame I've got...
View attachment 823792

Hi, the wheel rim needs to be central in the dropouts and central to the hub itself. This is achieved firstly by checking that the hub fits the frame and that the smallest sprocket is not sitting too far away from the dropout. In practice you won't have to start swopping spacers unless converting a hub from say 135 to 130/126 mm. The centralisation of the rim is controlled by the dish of the wheel and to achieve this shorter spokes are used on the drive side. Lacing is up to you, I tend to keep to 3 cross. The dish should be checked during the build with a wheel dish guage. You will need a wheel building jig, dish tool and spoke key to get started. The jig and dish tool can be diy built. Hopefully you will enjoy building your wheels and find it to be a very relaxing (and satisfying) pastime.

 

[Tootyred]

The problem will be weak wheels. The reason being that removing non drive spacers to fit a 130 or 135 hub into a smaller frame in essence pushes the flanges towards the non drive side as you cant alter the drive side spacing because of the cassette.

The result is the dish become much bigger and the percentage difference in tension between drive side spokes and non drive also bigger....not good.

If you use a spoke length calculator you can work this percentage tension out....

I suggest you buy this book....its a download. Its also plans for building your own jig and dish tool....

https://www.wheelpro.co.uk/wheelbuilding/book.php
It will also explain all the above with pictures far better!