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Bike Carbs - won't stay on manifold.
avagolen - 1/7/12 at 04:07 PM

As title.

How do you stop the silicone pipes from slipping off the carbs?

Len.


r1_pete - 1/7/12 at 04:38 PM

I replicated how they were fitted to the bike, i.e. sanwiched between the manifold and airbox.

zzr1100 race can airbox
zzr1100 race can airbox


myke pocock - 1/7/12 at 04:40 PM

These are the carbs on my Estelle trials car and they kept slipping off. Idealy the end of the inlet manifold pipes needs to have either a groove or a flange of some kind to retain the pipes (the carb will have grooves or similar). As you can guess mine didnt so I fitted the retaining strips either end and havent had any problems. It must work as those who classic trial will appreciate that if it can stand a pounding from a rough section it will stand anything!!!



Forgot to say that since the photo I have silicon hose and Jubilee clips instead of the bike clips.

[Edited on 1/7/12 by myke pocock]


avagolen - 1/7/12 at 04:55 PM

Thanks guys,

Boggs Bros manifold and zx6r carbs. Having trouble keeping the silicone hose on the carb.

Only a short mounting for the hose. It has a groove - as it it the bike carb,
but however hard I try to stop them slipping off , they do.

Retaining straps may be the answer. Thanks Myke P.

Has anyone used any ' sticky' stuff ?


austin man - 1/7/12 at 05:36 PM

can you put a bead onto the pipes ? of not drill out and put some rivet through it so the clamp goes over them


avagolen - 1/7/12 at 05:52 PM

Hi Austin Man,

Not really. The problem is the pipe is so 'slippy'

The carbs shape is designed with quite a tapered end to assist fitting and
the area to clamp on is only about 8mm - the same size as the jubilee clip.


whitestu - 1/7/12 at 06:05 PM

I don't know why the guys who make bike carb manifolds don't designt them to use the genuine bike carb rubber inlets. I use these on mine and have no probs at all.

Stu


macc man - 1/7/12 at 06:25 PM

A common problem, as said you need a pair of retaining brackets. I use 3mm alloy strip. Works fine.(See my archive)


paulf - 1/7/12 at 06:31 PM

I used normal black radiator hose and find it tends to stick to the manifold after a short while , it is also not slippery like the silicone and wont disintegrate due to fuel contact.
Paul


owelly - 1/7/12 at 07:25 PM

Can you get some narrow Mikalor type clips instead of Jubilee types? You'd get a tighter grip.


avagolen - 1/7/12 at 08:33 PM

Hi Owelly,

You may well be right, but as I tighten what I do have, they seem to squeeze the hose from the carbs.
My challenge is to stop the movement and get them tight all at once.

Even though it seems like a pain, I think the mechanical restraint system befor tightening
the clamps may be the only way to keep them all together.

Len.


owelly - 1/7/12 at 08:35 PM

How about a smear of Hylomar? Just a smidging and let it dry before you assemble.


avagolen - 1/7/12 at 08:39 PM

That may well be worth a try.

I can try a dab on the silicone to see if it 'grabs' or 'slips'.

[Edited on 1/7/12 by avagolen]


myke pocock - 1/7/12 at 08:57 PM

Yes, when you try to realy tighten the original bike carb connectors they can wrinkle the hose if you are not using the original hose connectors or the original design of manifold pipe end. I have actually ended up using two Jubilee clips on each end of tube (yes, 16 in total!!!!) with plenty of overlap of the hose. As I said though, I am classic trialling but have had no probs.


Andi - 1/7/12 at 09:02 PM

GPZ900r rubbers fit a treat on ZX6 carbs.
Mine were always falling off so I made a cradle which was more complicated than it should have been and a real PITA to get off.
Anyways the GPZ ones have never fell off (and I have sliding pillar boneshaking suspension)
Try your local bike breakers or here

Kawasaki GPZ900R Inlet Manifold Rubbers GPZ 900R GPZ900 900 R | eBay


emlyno - 2/7/12 at 10:59 AM

If you have a look at www.allensperformance.co.uk they sell all types of inlet rubbers. They are made in the correct material and supplied with clips. I had problems with my carbs falling off so made up some ally strip brackets to hold them on. (See photo in my archive) The strips allow the carbs to move so you don't have fuel frothing due to engine vibration.


FASTdan - 2/7/12 at 12:49 PM

Using 9mm Mikalors on the carb end (12mm on manifold end) and a correctly spaced and aligned manifold you should be able to secure the carbs. It can be fiddly and care must be taken to ensure the 9mm clip is aligned all the way around.

What size silicone and what OD are the carbs? Is it fluoro lined? Hose that is oversize will tend to cause more problems.

As to why the manifolds are not designed to use the original rubbers - one reason being half the carbs we get in dont have them so an alternative is required. On top of that there are multiple variations on rubber diameters, shoulder positions etc. Suddenly what was a relatively simple fabrication becomes more complex and more varied resulting in higher costs.

The manifolds do not require grooves in. with 20-25mm of engagement on the plain tube, using a correctly sized hose and a good quality 12mm clamp there is a huge amount of friction. As per the subject of this thread the only tricky interface is on the carbs.


avagolen - 2/7/12 at 09:34 PM

Thanks everyone for you responses.

The supplied Floroline silicone hoses are just a nice snug fit in the carbs.

The challenge is to get them to stay on while being tightened.

The carbs are chamfered quite a lot which helps get the tubes on,
but hinders the retaining of them as there is less 'flat' surface to clamp on.
Yes, the carbs are grooved and the hoses are slippery.

The manifold has gone back to manufacture for repair as I damaged it while tightening
the clamps, so when I get it back, I will try and assemble them better....

Len.


jacko - 3/7/12 at 05:31 PM

I have zx9r carbs and to stop your problem i super glued the rubber pipe to the carbs then used thin clips
on the manifold i used standard jubilee clips
I also put a wire from the middle of the carbs to a rocker cover bolt
the carbs have been on for about 4 years now
Jacko
Engine
Engine

you can just see the wire in this photo

[Edited on 3/7/12 by jacko]


Craigorypeck - 3/7/12 at 11:59 PM

The fluro lined ones were a great job on my zx9r carbs, they came with 4 8mm and 4 12mm jubilee clips. they also hold the charger airbox and pressure reg too, which isnt exactly light, never moved a bit. make sure all the surfaces are cleaned with leccy contact spray or the like to remove all oil. Id a mm or 2 smaller helps.

edit- piccy



[Edited on 4/7/12 by Craigorypeck]