1979 Triumph Bonneville 750cc, Swapping carburetors Part: 1 Amal Mk 1 removal

[@Segsy59]

Good to see the oil breather system ,mines a 79 T140d with the air box blanked off and routed to the rear. I'm going to stick a reed valve in but need to figure out what to do with the rocker box to oil in frame vent.

[@rickconstant6106]

Versions with the UK tank have a steel brace under the front of the tank, bolted to both sides to stop it flexing. Should this one have that (there would be a 5/16" threaded hole under each side of the tank)?

[@jessesvintagegarage765]

USA style tanks started the steel brace in 1973 when the T140 was introduced and was present from then on, and yes it was because the tank would flex and reportedly split in half and the bolts were 5/16 diameter bolt on each side holding the strap tight to the backbone of the frame. But as for the UK style tanks I am unsure on those what year they started, But the 1979 in this video does have the brace. The 1971 Tiger that I have videos on does not have the brace since it was before 73,

[@rickconstant6106]

@@jessesvintagegarage765 Ah, I missed that part where you removed it. Attention span is not what it used to be.

[@jeffuren6942]

Didn't the 79 have Mk2 carbs...?

[@jessesvintagegarage765]

Sure did, this bike ran really well with Mk1 carbs but my father really wanted to get proper Mk2’s back on

[@jeffuren6942]

@@jessesvintagegarage765 the NEW PREMIUM Mk1s..are supposed to fix all issues with older Mk1 I have avoided Mk2 bikes as I don't know the ins & outs

[@billg125]

That has GOT to be the best thing you could possibly have done!! Mk1 concentric carburettors are diabolical thing's. Mk1.5s are better but, still suffer from distortion etc. Mk2 which are clamped on to their inlets are the answer. That is, not-with-standing fitting Mikuni's.

[@jessesvintagegarage765]

Well, we like the Amal Mk1 carburetor real well, and if you don't over tighten everything, they work very well. We only swaped the those Mk1's out because we wanted to put the Mk2's back on for originality. And wanted the Mk1's for another project. As far as mikuni's go, we have a whole large box of them from various bike's we've bought, and to be honest, we just dont like anything about them. The mikuni is a lot wider than the Mk2's and wouldn't fit right with the parallel port style head this 79 model has and they hit badly in the middle so much that the original air cleaners don't line up. When I bought this Bonneville, that's how they forced everything in there, and they cut the air box covers so they could get it to fit. It was a total mess.