1970 Thunderbolt
Just wondering if anyone has got a diagram or could do me a photo showing the order of assembly for attaching the rear shocks and support rail to the main frame. For example does the support rail go outside or inside the frame or as I suspect in the little nook with some sort of spacer.
I'm pretty sure that the way it's put together on my project bike is wrong. It's certainly different left to right.
I've tried working it out from the BSA parts list and workshop manual, but to no avail.
It's amazing how basic things like this are so frustrating.
Many thanks if anyone can help.
I've worked out that the support rail must attach outside the frame.
First of all, happy new year to all members.
Made some pictures maybe this helps, 1970 model.
Thin spacer between bracket on the right.
Long spacer between bracket on the left.
Don't mind the alloy brackets, they are for the racing seat.
Hi,
What is the story behind the 90ยบ manifolds for the carbs?
Dave.
Quote from: Gup holland on 01 Jan, 2025, 10:43 First of all, happy new year to all members.
Made some pictures maybe this helps, 1970 model.
Thin spacer between bracket on the right.
Long spacer between bracket on the left.
Don't mind the alloy brackets, they are for the racing seat.
Thanks so much. That's fantastic. Just what I need.
Glad to help you Patrick, That's why i joined this forum,lots of info here.
About the 90' manifolds , this starts about 30 years ago so i hope i Can recal my memory. After my frist engine rebuild back in the 90', with a Rebore and new forged pistons in it(high compression) the engine starts to (pinking you call it) When the engine was hot. Specially with hot weather. Carb and ignition settings didn't make any diverance..
After a ride the carbs went realy hot, whatever i did with insulating gaskets and so on. Knew ,had to cool down the carbs because the air stream did heat the carbs.
Made some manifolds and TIG welded it.
This Made an imediatly diverance, exept in very hot weather it sometimes hapend.
Then i saw an original Lightning head somewhere and Then i realised my head was to Many times skimmed off, by former owners.
So i Made a headgasket from 2mm koper plate. This helped much to lower the compression to acceptebel level.
After this no problems anymore. I rode it for 30 years and on, now the bike is for another rebuild after many miles. Frame respray, new wheels etc etc..... and the engines is also rebuild. The carbs and manifolds will go back.
I like to give the bike a personal touch. It has LED pinkers/lights, oil temp and pressure gauge on. I shall never win a price for orginal bikes, but I do not mind.
This is the story in a nutshell.