Carburetor fitup

Today was the second time my brother and I tried to get the carburetor to really fit in the boot but it just doesn't want to go. This second time, we even greased the carburetor, and it still didn't go in.

I have the Mikuni carbs on my X, so I don't know if they are different than the Hitachis as far as the fitup.

My question is, how far are they supposed to push in to the boot? I can only get the first ring in, and with two people pushing, they won't go any further. Does anyone have a picture of how far their carbs go in?

Another fitup issue is that one of the fittings to the airbox is loose in the airbox. The other three fittings feel rigid to the airbox, but this one "rattles" around in the airbox ring. Is this going to cause the symptoms of a vacuum leak since the air could bypass the filter for that cylinder? Does anyone else have this problem? If so, what is the fix?

 

Boots have a lip inside them that should match an indent on the carb. They should fit in reasonably easily. Sounds like the carb opening is too big for the boots. Try measuring the boot lip to edge and put a texta mark on the carbs the same distance back from the indent to give you a line to work to.

As for the carb to cleaner boot, this is not such a big issue. An air leak on this side will make minimal difference to the running of the engine. You should get a new boot for it though to prevent dirt or water entering.

 

richard03, here's a picture.... hope it helps!

My carbs are very tight to get into place, could be the cold or age of the rubber, not much flex to them anymore. Next time I'll try to warm them up before putting the carbs on.

The air cleaner box side rubbers could use some silicone to help seal them, but use very little cause one day you will need to remove them. As Hired_Goon says not a big issue on this side of the carbs, as long as it's a very small clearance.

 

Thanks very much, the picture helped. I must not have had mine in far enough then, because I could still see that indention on the carburetor.

But, like I said, we greased those things, and had two people pusing on them, and they didn't move in. Bummer.

I will try heating them next time, that is an excellent idea. It might also be easier for me to take the stupid rubber off the engine, put them on the carburetor, and then put everything back in.

 

try putting the bottom half in (or top) and while pushing, rotate the carbs into place.

Hope your only going to use a hair dryer or something similar to heat the boots up..... not open flame!

 

Richard I install my carbs with a long board 3/4 of an inch thick and about 4 feet long. I place it behind the carbs and slip one end of the carb rack in place then holding it press the other in using the leverage of the board. You have to constantly check your angle and make sure the carbs are aligned with the intakes. Works quite well for me. I tdidn't however work the other night due to the cold temps so I tried during the day after heating the intakes with a drop light and viola!

 

Good ideas. I was planning on using my wife's industrial strength hair dryer. I was using metal crowbars, but that doesn't help much since there is nowhere to put leverage on except for the plastic airbox. Are all bikes this hard to put in and take out the carburetors?

 

I used the same trick that bluemaxim used. A scrap piece of 1x4 that happened to be laying there in the garage. I thought of a prybar, but didn't want to take the chance of damaging the throats of the carbs. It is a tight fit to get them on. I believe that even in the eighties, engineers were trying to figure out ways to keep us mere mortals from working on our own equipment. Of course they probably didn't figure that 20-some years later, we would be reviving them from the dead and riding them still. Ha! jokes on them. :lol: Or would they be proud that they designed such a fun and wonderful bike, that we would want to keep them running as long as we have?

 

Getting the carbs back on my 900 was a very tough job. Stick with it. It sort of rotated them in, getting the rightmost carb started then moving the bank inwards from right to left.

 

Silicone grease and the lever trick should do you. If it is such a bear to push in, odds are age is setting in and hardening the rubber. You might want to start saving up the $100 or so for new ones in the near future. A bit of grunt is needed but use some finess, don't hammer on it. Good luck buddy!

 

I just fit my carbs in today, and I had the same problem. I didnt want to pry on anything, so I got creative.. Just took a ratcheting tiedown strap, looped it behind the carb bank (just under the tie bar), hooked it onto the downtubes on each side of the engine, and started ratcheting it down. The carbs popped right into the boots with very little complaining.