connecting airbox to carb

[richmond]

I have just stripped/cleaned the carb and replaced the airbox with new. Carb is back in. airbox in place. but I cannot get the 3 rubber boots on the airbox to connect to the carb - every time I try to fit, one of the boots twists/gets caught/moves out of alignment and fails to go on. It is driving me mad - I thought this would be the easiest bit?

Any hints or tips? Thx.

[Mustang]

lift the carbs up slightly and then jam the airbox on so that all three rubbers slide over the mouths then while holding the airbox in place tighten up either the leftmost or rightmost hose clamp on the air box and then get the rest .......................
or another way that works good is to don't shove the carbs all the way into the boots on the engine and get the air box clamped down first then finish shoving the carbs into the engine boots


WD 40 on the rubber boots helps a lot !

It gets easier the more you do it

[JetdocX]

I would add that you make sure the clamps are loooooooose.  Getting them apart is much easier than putting them back in.  Funny how sex works like that, too. :lol:

[richmond]

Thanks for the advice. I already tried all of the things you mentioned earlier except for the WD40 - so I will try that in the morning (I'm packed-up-frustrated for the night now..).

[cascadetiger]

I used a light coat of grease. Eventually I found that placing the mounting screws in on the air box forced the rubber boots onto the carbs. Then I tightened everything up and the rubber boots were tight on the carbs. This is the worst part of the job for sure.

[nightrunner]

Yup, coat the inner edge of the boots with vaseline or wheel bearing grease.  Do both the airbox to carb boots, and carb to head boots.  Carbs pop in and out easy.   Apply once and you are set for years.  I would not use WD; too thin.  The grease will also make for a better seal.  Rubber gaskets and O-rings need to be able to slip against the metal surface a tiny bit rather than stick to it.  

Another trick is to rig up a support so you can work on the carbs suspended on the side of the bike.  That way you don't have to undo the throttle cable.

[richmond]

Vaseline did the job - I feel a bit stupid for not thinking of that one!
Anyway, it was all to no avail, because after getting everything back - it is still running as rough as an old dog at anything under 5000 rpm. I cleaned the carbs (and had to deal with a spinning captive nut before getting that far..), have checked the coils, replaced the air filter and everything was just the same as before...what a waste of time..

[Mustang]

did you take the pilot jets out of the carbs and physically look thru them to confirm that they are in fact open ? you should be able to see a little pinhole when holding up to the light .

the pilots have a big influence on the motor under 5000 rpm
are they mikunis or keihins  for carbs?

and if you are 100 % certain the carbs are clean with no blocked passages , then it is usually the coils even if they test fine and show a spark

especially if they are GILL coils
you will swear on a stack of bibles that you have a carb problem but it is the coils they fail under a compression load
if you have a weak faint spark that you can barely see when you hold a pludg to ground against the engine it could well be the coils

disclaimer : it's hard to diagnose others problems from across the ocean

[richmond]

I have Mikunis. I have to admit to stripping and cleaning all components except for one pilot jet on one carb - I just couldn't shift it - either in or out - and convinced myself at the time it would probably be alright (even though I knew I should probably perservere). After what you have said I am now preparing myself for having to pull the carbs again (oh great, can't wait..) recheck the other pilot jets (although I am certain they are ok), and work out how to shift the 3rd and stubbon pilot (any tips?).

I tested the coils using a multimeter, and all readings were spot on with the numbers listed in the Haynes manual. They are PVL coils.

I Haven't pulled the spark plugs for the simple reason I didn't have the right size socket (why does everything have to be so unnecessarily difficult on this bike) - so will need to try and locate this on Monday when the shops open. I got as far as pulling the lead from the right hand side plug, and it made no difference to the rough running, so I guess this tells me something, although I am not exactly sure what yet!

Thanks for your response to my posts - it makes a big difference in preventing me just setting fire to the bike....

[Mustang]

was the right side carb the one you couldn't get the pilot jet out of ?:?:
and I have a couple of coils kicking around here that test fine on the multimeter but are still junk . bike runs terrible with a bad misfire like a complete missing cylinder until the tach hits 4500 rpm , I was convinced it was carbs but the new nology coils fixed it .

[nightrunner]

Mustang is not the only only one.  My coils "ohmed" out just fine too but were shot.  I do not fully understand it but somehow they can check out on the bench and then fail when the alternating load (electrical) is applied.  The fact that a lot of them will fire at high RPM but fail down low suggests something goes wrong with the induced magnetic field as opposed to just an open circuit.    

Nology seems to be the popular fix, but a few of here have gone with swapping to TT600 coils.  The actually sit on the plug so they is no plug wire.  Picked up a set of used ones on ebay for like $30.  Runs like a champ now.

[richmond]

I finally got hold of a spark plug spanner that fitted. Replaced all three plugs - but still appear to have a problem on number three - if I remove the plug lead, there is no change (whereas removing the plug lead from one of the others will stall the engine).

Basically, I still have the same problem of engine running real rough under 4000 rpm. I swapped both #1 and #2 coils onto #3 cyl, but that made no difference. Does that rule out the Coils being a problem, or is it normal for all three to crap out real quick?

I would rather be sure before I lay out a chunk of money on new nology's.

Could it still be the pilot on carb #3?

Any help pleae? I so much want to be on the road now instead of stuck in the garage...

[Mustang]

I would rule out the coils ......
have you checked valve clearances lately ? if the intakes are gone to zero clearance on that cylinder it won't run on that cylinder
and are you sure your plug lead is good try swapping the plug wires .

[richmond]

Swapped over plug leads, so they can be eliminated.
I haven't checked valve clearances - bike has done 20k miles so is due for a check soon anyway. Does this now sound more likely than a carb problem ? (I did clean the carbs before, only thing I didn't do was the pilot jet as I couldn't get it out)

[Mustang]

Does this now sound more likely than a carb problem ? (I did clean the carbs before, only thing I didn't do was the pilot jet as I couldn't get it out)

if you never cleaned out the pilot jet hole there's your problem 9 out of ten times

I thought we went over this already ..............clean the pilot jets and pilot jet circuit
it won't run below 4000 rpm until you do

you are just wasting time doing anything else until you pull the carbs and make sure the pilot jet circuit is clean