Topic: CB750 K2 - Reftting or fitting new carb boots

[nancy]

Hi  - my 1st post to this site. My K2 is running OK at highway speed but a little rough during city riding at around 50kph. I have removed and cleaned carbs, checked and adjusted float levels and was about to attempt to run a synch on the carbs when I note that the boots that mount the carbs to the head seem to but up against protruding flanges. I wondered if the boots should be fitting OVER this flange. Only reason I noticed is I have never been able to align the airbox with the mount holes on the frame - the holes on the airbox are past the holes on the frame and I have to force the airbox back to the motor and down on an angle...which means the side cover impacts the airbox and can't be fitted properly. I can't force these boots over the flanges and when I check Honda service manual, the pic seems to show them seated as I have them - butted up against the flange. I'm thinking of ordering new boots from Davis Silver spares, but can't find reference to correct fitting. Anyone?
Regards
Mark

[Duke McDukiedook]

New boots, and they do fit over the flange.
You will buy two #1 and #2, they flip over to become 3 and 4.

[nancy]

Thanks for advice - will get new boots when the minister of finance isn't looking..

[nancy]

Did I explain this right? I meant,...when fitting boots onto the intake, there is a hex-shaped "flange" hard up against the head. My boots are fitting neatly over the cylindrical section of the intake and snug up to the face of the hex-shaped "flange". Are you saying that the boots should extend over these raised flanges and be snug up against the head?

[Spanner 1]

No.....not over the hex at the head but against it as you describe. Hardened boots at the carb/head and carb/airbox can distort the mounting set-up, pretty common and making it a chore to line-up the box mounting flange bolts...... never had the luxury !, but new boots would make it all much easier to work with. Do a search about 'boots' on the Forum tho', guys have had success softening the boots for easier fitting carbs/airbox....

[nancy]

Thanks Spanner1. I have seen those posts and have in fact spent the last hour simmering a brew of hot water with 5ml of Wintergreen oil added. It does soften them somewhat. I'll cook them some more tomorrow and have another attempt. Not easy to source new parts here in NZ - have to get them shipped via UK or US and shipping costs for bigger parts are outrageous. I was quoted US$60 to ship US$60 of parts!
Regards
Mark
PS: Do u know - are those boot fixing hoops/bands NOT interchangeable i.e. different sizes front to head vs back to carb? I have the front set missing and a set of wider hose clips have been sub'd in place and I tried to fit the clip from the rear end to find it was loose on full tighten.

[Spanner 1]

I'm not aware that the boot clamps are different carb end or head end. The clamps on mine are tightened all the way too, may be normal.....the wider hose clamps may have been 'torqued' more and have flattened the boot so the org. clamps are now loose when fitted in their place...?

[lordmoonpie]

The boot clamps are the same front and back of the rubber manifold, no difference. Softening even new rubber manifolds in boiling water is a big help to get them on. Soften them up, dry quickly and shove them straight on. Because I have the nightmare of keihin CRs as well I usually pull a muscle somewhere shoving them on LOL!