Plenum problems help needed

[Mike750]

Hi all as title says I’m have problems with my plenum on my 750 Gsxr 89 model, it has the oval mouth carbs , I’ve made a plenum cut out the holes and used standard carb rubbers but I can’t get the rubbers to fit good and think when there’s any boost there just going to pop off, is there another method I could try with my carbs , if I have to start again I will just trying to do the job myself at home but finding it a pain to get things sealed properly, thanks for any help it’s well needed 

[Gixer1460]

What don't fit good? - rubbers to carbs or rubbers to the plenum? Can't understand why rubbers to carbs would be a problem as they are designed to fit together, ok not under boost conditions but it's usually not a problem if correct clips are used. But if the latter, then i'd suggest remaking the holes for a better fit - this is the only bit you can control. There are plenty of builds that use OEM rubbers, so they do work. Other solution is thin wall silicone hose that is stretchy to accommodate oval and round pipe shapes but they do suffer with slippage if a bit of oil gets inside them! 

[Mike750]

It’s the rubbers to carbs is the problem there was a curve in the standard air box that I can’t seem to get right, so each boot has a different part number, either I can’t get two and three to fit properly or one and four, I even ordered two more rubbers (two and three) to go with the curve better  but still can’t get it quite right, I say il just have to cut off the bass plate again and try and adjust 

[mikeyd]

Any pictures?

[Mike750]

I might get chance to take it off again this week il put a few pics up , thanks 

[colinworth79]

normally just have a round tube coming off the plenum and then the hose takes up the slight difference in shape . i assemble the pair together on the bench then fit to the engine as one unit .