Hi I’m a few weeks into a rebuild. I’ve Just about got the frame stripped down so I can get it powder coated then I can start putting the bike back together. I’ve got bits and oil everywhere but feel it’s going ok but I could do with some advice on having the cylinders rebored they seem to have some rings of corrosion half way down I’m assuming it’s where the rings have sat for decades, I think it’s a standard bore the pistons haven’t got any + identification on them but I’ve got no way of measuring them. I’ve put a couple of photos of the barrels in the pictures.
By the way just so you don’t get confused the bike has T140 engine and frame numbers but sometime in the past someone has installed a TR7 cylinder head
Jim My advice would be to get new barrels complete with new pistons and rings. It saves all the fannying around trying to find an engineering firm close enough, not too busy (nearest here has about a month waiting list) and know how to do it properly. My last barrels came from Brit Bits - great service, pretty good casting and fit was perfect. I've got one of those Bonny engines with a single carb head, it was the thing to do in days gone by - easier to tune and less fuel apparently. I like the twin carbs though so have converted back to two carbs using ported webco castings. The carbs stick out more as the angle is greater - looks a bit weird but it's on the chop so that's ok then.
Hi Jim, I'm sure when @darkman see's this he'll give you some good advice as he's the classic Triumph genius on here.
There are two options Jim, re bore and new pistons and rings if you have a trusted engineer, £200.00 ish or New barrels pistons and rings for £400.00 inc from L F Harris
Thanks for the reply darkman I think the way this bike is hoovering up cash it will have to be the cheaper option a rebore
She looks a bit beaten up yes, but some love and care, you will get her there keep the updated coming, nice to see how it’s coming along
Forgot to add @Jim Hargreaves darkman has done a few restorations on here take a look back over his old posts and be amazed
If you want to go with the webco castings to get those twin carbs back on (rather than replacing the head) - here's what they look like. A bit sticky outie.
Not a bad idea but I’ll just stick with the Tiger head for now I’m trying to keep costs down I didn’t realise how much money these kind of restorations would eat up
I know what you mean I’ve been trying to find an engineering firm near me who can do the job but up to now I’m out of look. New barrels and pistons might have to be the option
Hi everyone Has anyone got any tips on removing the timing side crank main bearing it’s so tight to the balance weight I can’t get anything behind it.
There is a specific puller for them if you look online i think you can still buy them for around £70.00. The other option is to heat the inner race quickly and use wedges.
Jim yep, as darkman says heat is your only option if no puller is available. Watch Todd of Lowbrow Customs doing the heat thing here - it's about 33 minutes into the video well worth keeping the whole set of videos from Todd always good to reference back to them.
