Tricks to mounting carbs with hex nuts
- Thread starter okwebb
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For that matter - slotting the inner carb mounting holes would be an easy five minute mod with a Dremel or whatever. 
Tornado
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Thats a pretty neat trick. Details on the mani mods and rubber connection?
Also see that you've got the balance tube spigots coming off the underside, not top side of mani. Had to look twice to see if manis were upside down.
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I very much like the idea and your implementation. I have 2 concerns that you may have gotten past and would appreciate any insight on these:
1) The carbs with rubber connectors have considerable less support than the OE design; has this or does this cause rubber fatigue?
2) Does the gap between the 2 sections of manifold induce any unwanted flow characteristics?
Best.
htown16
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That looks like the rubber connector Triumph used on the T140E bikes with the Mark II carbs and parallel port head. My 78 Bonneville has those and I've only replaced them once in 15 years. They are pretty thick. They also are stepped inside so the carb can only be pushed in so far. That way the gap between the carb and manifold is the same diameter as the carb throat. Triumph Tridents and BSA Rocket 3 also use a similar system.
Yes they are Amal 1:5 rubber manifolds ,the alloy inlet where bought from RGM the balance tubes came fitted underneath.There has been a thread on here about up or down balance tubes general census it doesn’t matter .I had to cut about 4mm of the manifold so the rubber would fit in the groove properly,(hacksaw and big file)
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SteveBorland
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Interesting setup here - any more photos or details on how you did this?
I have a set of manifolds intended for rubber mounting, but they are rather poorly done.
Buy the mk2 manifolds RGMs need-finishing but you can blend them into your head and manifold. The top edge in photo is what I had to shorten,the manifold came from Amal ,complete with o rings bolt this to carb need button Allen, not much torque so not a problem .I used phenolic heat washer on manifold with gasket either side and blue hylomer just to be sure . I am no engineer ,but couldn’t believe how easy it was and why no one is making a kit.
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my 74 Mk2 has allen head cap screws at the carb mounting flange. i use a 1/4" drive allen ball-end hex socket. it's a bit tricky, but can't say i've had problems removing the carbs. https://www.mcmaster.com/54075A49/
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Balance tubes at the underside is a disadvantage in my view. I have some manifolds off Triumphs here which have that arrangement. All balance tubes were clogged up by fuel debris and corrosion residues.
- Knut
