Mikuni mounting - to bracket or not to bracket

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fast_eddie

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Location
SYDNEY
RS36s on a 1200

I notice that my set of Miks gets pulled closer on the right hand side (due to the throttle cables) so effectively they are on a slight angle on the horizontal plane.

Despite a few attempts to tighten the hose clamps I cant seem to stop them from doing this, I have now probably over tightened and cracked the rubber boots.

I remember reading a thread saying you shouldn't put a metal bracket on as the carbs need a bit of give (or I guess bounce).

A cable tie looks kind of shitty and doesn't stop the carbs shifting around on the vertical plane.

Any thoughts on this?
Hope I'm making sense.
Cheers
Ed
 
Keith made a mounting bracket off the rocker box for them a few years back.Try searching on his name for the thread. Mine are held with a couple of large 300mm cable ties from above off the frame. Mine were slowly moving rearwards out of the rubber manifold before these ties were fitted although I have a very different manifold angle cause of the way my head is ported. Older Triumph twins that had rubber manifolds needed to have there carbs supported by large rubber O rings off the frame. Any mounting should have some give in it to avoid fuel frothing from vibs,even if Laverdas dont vib,mostly. This is something Brett was going to look at , he is building a set of FCRs for his Cico at the moment. Hope he is feeling better, missed a ride on Monday, must be crock to do that.
 
Tried searching for Keith's post about the brace he made off the rocker box. Couldn't find it. Its defiantly here somewhere.
 
fast_eddie said:
A cable tie looks kind of shitty and doesn't stop the carbs shifting around on the vertical plane. 
Click to expand...
They do if 4 cable-ties are used, as on Clyde.  It's all about the vectors.
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, ok Ed, are you saying I do some real shitty work?  well,,  are ya??  ???
It's been working well for many years and miles.
 
I used an angled set of inlet rubbers off a snowmobile that I got from Wolfgang, seemed very stiff and rigid when I fitted them but they fairly quickly became quite floppy in use. Twice I had a problem with backing of after a full throttle squirt, the back pressure was enough to actually blow the Mikunis out of the rubbers. Very embarrassing when there's a bunch of Harley riders watching.
I made a bracket to hang the carburetors from the top tube, used the threaded hole on the middle carburetor and a strap wrapped around the top tube. No further problems, but I would like to pick up a set of Red's angled stubs one day, the snowmobile rubbers are just too floppy.

Ken
 
I think a rigid bracket from carb-to-frame might be a bad idea, as the 2 will move relative to each other and 'work' the carb rubbers.

Better is carb-to-engine.

The zip tie mass support is pretty good in the fight against gravity.

Just my 2p...
 
If your not desperate to use pod filters the standard airbox and rubbers holds them in place as snug as a snug thing. Maybe not the best for outright power but looks nice.
 

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Not RS's but Keihin CVK's  also using standard air box & rubbers, but rubbers turned back to front. Home made inlet manifolds so the carbs are as close to the engine as possible to allow everything to fit.  :D
 

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