PDA

View Full Version : Bent frame advice/opinion

dunlop0_1
08-Jan-2013, 17:40
I knew the frame was possibly out of sorts so I did few checks today. Head angle/alignment seems ok but as you can see in the pictures there is a definite twist in the frame.
Is this worth repairing?
Got a quote from a local frame straighteners, £150 just to check it. :o
No thanks.

http://i139.photobucket.com/albums/q289/dunlop0_1/Photo0056_zps0139e293.jpg
http://i139.photobucket.com/albums/q289/dunlop0_1/Photo0058_zpsf20fdde9.jpg
Shazaam!
08-Jan-2013, 18:41
You're using the wrong datum by supporting the frame from the external bosses for the engine mounts. Exact alignment of the engine to the steering head or rear suspension is not critical.

You need to check alignment of the front and rear suspension mounts by supporting the rear suspension mounts internally using a bar passing through the holes (not the external boss surface) and verify that the pin through the steering head is vertical.
dunlop0_1
08-Jan-2013, 19:03
You're using the wrong datum by supporting the frame from the external bosses for the engine mounts. Exact alignment of the engine to the steering head or rear suspension is not critical.

You need to check alignment of the front and rear suspension mounts by supporting the rear suspension mounts internally using a bar passing through the holes (not the external boss surface) and verify that the pin through the steering head is vertical.

Thanks, will do
skidlids
08-Jan-2013, 22:40
Yep as Shazaam says make sure the steering head is perpendicular with the actual swingarm pivot

unlike the poxy swingarm JMC made for my Harris years ago, Ok the pivot was as the frame was straight but the rear wheel spindle wasn't as they couldn't even get them aligned correctly.
Quarrybends
20-Jan-2013, 08:25
as the saying goes "pay peanuts and get monkeys" the equipment used isn't cheap and will give you peace of mind, wont be much more to jig it if bent as it's set up and in situ.
dunlop0_1
20-Jan-2013, 08:36
as the saying goes "pay peanuts and get monkeys" the equipment used isn't cheap and will give you peace of mind, wont be much more to jig it if bent as it's set up and in situ.

Of course, but it was the "about" part of the price that put me off. I couldn't pin him down to a definite.