Measuring the Barrels and Pistons of My Barn Find Triumph T140 Bonneville Dessert Sled | 06

[@BlairGuinea]

Great vid Sir, good to see some one actually knows what they are talking on youtube, a big thank you

[@SPANNERRASH]

I appreciate that! I hope I live up to what you say, I only try to pass on things that I know from my own experience. But sometimes I will be wrong :(

[@BackToTheeighteens]

Great video lesson! Thanks for sharing

[@SPANNERRASH]

Thanks for watching I'm glad it was useful.

[@markgenest6206]

Enjoy your videos. Informative! I was looking forward to how you are going to separate cylinder and head. Next time!

[@SPANNERRASH]

I am still contemplating putting them in a hydraulic press. But I am not going to rush into anything that might be destructive. I am going to give them a good dose of patience for a while, that along with some lubricant and occasional heat, I do have a lot of other things to give attention to on this bike! :)

[@karlvanboxel561]

@@SPANNERRASH u may have heard of the 50/50 atf and acetone mix as a penetrant I tried it recently worked great

[@SPANNERRASH]

Trying paraffin (us kerosene) at the moment, but may give acetone/acf a try next.

[@stephengibbs4372]

Also has it got alloy barrels? I thought only the Harris ones had them, they were nickasil and can’t be bored.

[@SPANNERRASH]

I'm pretty sure the barrels have steel liners and are pretty much standard, not plated.

[@stephengibbs4372]

@@SPANNERRASH a friend bought a Harris tiger 750 new and it had porous cases and after it was apart a few times trying to stop oil leaking I pulled out a barrel stud. We ended up painting inside the cases with orange etch primer and put iron barrels on it. Also alloy barrels used a composite head gasket on them, explains why stuck. Good luck with it . I’ve had a 76 bonne for 30 years

[@SPANNERRASH]

Thanks for the info. I can't wait to get to the point that I am worrying about oil leaks :) Hopefully not too many.

[@karlvanboxel561]

I quite enjoy the metrology part of it my self I used snap gauges and a a micrometer on the new brg inserts in my FZ 750 cases measured thd crank And did the maths I had to swap several brg shells about to get the correct clearance but as I was using a different crank in the cases I didn’t really trust the crankcase hyroglyphics and the stamping on the crank that’s the way I did it very pleased with the result

[@SPANNERRASH]

It's great when you measure things and it all makes sense. I know what you say about the stamps on the cases. Who knows what has happened to them in the 30 or 50 years since.

[@ianbooth4255]

0.9mm is just shy of 4 thou, which is perfect. A quick hone and new rings and you're good to go. Have you got that head off yet? I think by now I would have welded a nut onto the studs to try and remove them, having repeatedly soaked them in penetrating oil. TBH I wouldn't have removed the engine until I'd got the head off. Great project.

[@SPANNERRASH]

Thanks for the encouragement, there's even more to think about with the barrels and head, something I hadn't realised in this video :) I am going to do the engine and rolling chassis concurrently so I don't want issues with the engine stopping me getting on with the chassis.

[@RobBrookbanks]

Re: getting the heads off, try getting white vinegar down the stud holes and letting it soak. It should dissolve the aluminium oxide which is the problem. Anything poured down the bores isn't going to help in this case.

[@SPANNERRASH]

Thanks. I will look into using the white vinegar. I have used it for cleaning tanks etc in the past, never thought of using it here.

[@jamesrichardson1901]

Another reason to pay attention in maths.

[@SPANNERRASH]

Hopefully your comment isn't saying that I didn't pay enough attention at school. :)

[@matthewharmer1656]

Whats the point of measuring when you can get the head off? You dont know what the top cylinder is like...

[@SPANNERRASH]

If the bores were worn out, and the pistons had too much clearance then looking for other barrels and pistons might be quite reasonable. However as it doesn't seem that the bores are worn, and the pistons seem to have an appropriate clearance it is worth making an effort not to damage the barrel. I suspect you mean I don't know what the top face is like and whether it would need machining, but as it stands if they would just come apart I suspect the top would be fine. However I may cause damage in my efforts to split them. At the moment I feel that it is more important to protect the head ( the more expensive component ) than the barrels. However if I can reuse both that would be great. If the barrel where completely useless I could contemplate sawing them off :)

[@Pokemongold88]

I started watching earlier and your video disappeared 😆

[@SPANNERRASH]

Sorry about that. Happens sometimes. Seems to be OK now.

[@terryrance2662]

Will you be testing the rings to see if they've been gapped properly or get new rings?

[@SPANNERRASH]

@@terryrance2662 At least check, but probably replace

[@stephengibbs4372]

Please stop knocking the conrods on the cases, if they get marks in them it’s where they’ll break. I put alloy rods under the pistons front to rear and sit the pistons down on them and once pistons are off I put toilet paper cardboard rolls over the rods.

[@SPANNERRASH]

Good advice and I do know better, now the pistons are off I will be putting a cover over them. I do intend to give them a bit of a polish when I start putting it all back together. Cheers.