Author Topic: what's the secret to installing 550 carbs?  (Read 1431 times)

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Offline Don R

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what's the secret to installing 550 carbs?
« on: July 28, 2019, 07:18:00 PM »
 Hey 500/550 guys, I got the carbs off with great difficulty and got them clean. Is there a secret to putting them back on? The airbox rubbers are pretty soft so that should help.  It reminds me of fighting the carbs onto a KZ1000.
   The 500/550 manual says loosen the airbox bolts, and the carb and filter clamps then remove. It didn't seem that simple.  Maybe because it's got a sidecar, doesn't fit on our trailer and I had to take them off in a gravel driveway.
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Offline goodtryer

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Re: what's the secret to installing 550 carbs?
« Reply #1 on: July 28, 2019, 07:43:35 PM »
I saw a thread or 2 about using tie down straps wrapped around the carbs and the engine to pull them into place.

I’ve been able to just wrestle mine on so can’t speak to actually using this method.

Good luck
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Offline carnivorous chicken

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Re: what's the secret to installing 550 carbs?
« Reply #2 on: July 28, 2019, 08:22:52 PM »
First thing to do is be glad it's not a 350F.

I've used tied downs attached to the forks, so you can wiggle the carbs back and forth a ltitle and pull them in. Also a 2X4 across the back ofthe carbs, but be careful not to use too much force.

Offline flatlander

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Re: what's the secret to installing 550 carbs?
« Reply #3 on: July 28, 2019, 11:08:14 PM »
pretty much any way you do it it's a pain in the arse. loosen all the screws on the airbox so that it can wiggle around a bit. and stick the rubbers back into the plenum so just their ends protrude out of their holes, which also gets you more room to get the carbs onto the manifolds. use wd40 or similar to make them go more easily onto the manifold rubbers.
then what i did: get the rack in there, get it as close to its position on the manifold rubbers as you can. it won't go completely on, just close. then i positioned myself at the front, sort of embraced the engine with my arms, holding the carb rack up and pulling it forward at the same time. you'll need to pull like a real mofo and definitely need to curse out loud in the process. once you struggled and cursed enough the carbs will be on, and you can pull the rubbers out of their holes in the plenum and attach them on the inlet side. then do some more coursing, open a beer, look at the installed carbs and say "never again". after you somewhat recovered from your struggle, you can bolt the airbox back in place, attach the cables and do other easy things like that.

Offline chrisbc55

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Re: what's the secret to installing 550 carbs?
« Reply #4 on: July 28, 2019, 11:10:08 PM »
I use some silicon spray and wriggle away until they slip on

Offline brewsky

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Re: what's the secret to installing 550 carbs?
« Reply #5 on: July 29, 2019, 01:56:07 AM »
On both my 550 and 750 I found the following method makes it easy:

Tank and seat off
bike on centerstand, (with stand tied to front with ratchet strap to keep it from rolling off)
heat rubbers with hair dryer
lube with silicone or wd40 or the like
straddle the frame
rock the rack up and down while pushing forward with one hand on each outer carb
you can feel them pop in place
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Offline Mushman

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Re: what's the secret to installing 550 carbs?
« Reply #6 on: July 29, 2019, 03:09:03 AM »
What brewsky said...I used a hair dryer to warm up the carb boots too, it definitely helped them slip right on.

Offline Scott S

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Re: what's the secret to installing 550 carbs?
« Reply #7 on: July 29, 2019, 03:28:24 AM »
 Loosen the clamps a lot. More than you think you need to. I find that on the manifolds it even helps to loosen the ones on the engine side a bit. I use some white lithium grease in the manifold rubbers.

 Remove the two bolts on the top of the air box that attach to the frame so the air box can slide back. If your air box rubbers are in decent shape, I remove the two outer rubbers. They came be squashed and installed once the carbs are in. Just be sure to line up the tang on the rubber to the dot on the air box plenum.

 If they are PD series carbs, install the choke cable and throttle cable(s) when they're about halfway in. Much easier than trying to fish them in later. The early carbs, throttle cable(s) are not an issue.
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Offline scott jones

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Re: what's the secret to installing 550 carbs?
« Reply #8 on: July 29, 2019, 05:01:43 AM »
I found it to be difficult to but like the previous response. Just move the air box boots back into the box as far as you can. Just don't do like I did and pop them into the airbox. LOL. That will give you just enough room, Still a pain in the butt.

Offline Don R

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Re: what's the secret to installing 550 carbs?
« Reply #9 on: July 29, 2019, 06:58:05 AM »
 :o  Thanks, I was hoping for the secret easy way, tucking the stacks into the air box must be it. They are the PD carbs. The outers are dented, a PO must have gotten a little carried away.
  My brother bought a manual at Davenport's swap meet last year.  I was so disappointed when it just said loosen the clamps and then remove the carbs. 
« Last Edit: July 29, 2019, 07:01:17 AM by Don R »
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Offline TwoTired

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Re: what's the secret to installing 550 carbs?
« Reply #10 on: July 29, 2019, 08:27:54 AM »
There is an install procedure in the FAQ. FYI

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Offline Don R

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Re: what's the secret to installing 550 carbs?
« Reply #11 on: July 29, 2019, 10:40:54 AM »
Thanks TT. I'll give it a read.
No matter how many times you paint over a shadow, it's still there.
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Offline jakec

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Re: what's the secret to installing 550 carbs?
« Reply #12 on: July 29, 2019, 10:50:36 AM »
I just did this on wednesday.

1. Use a cam strap in an X pattern to tie the airbox BACK and UP in the frame. Keep the rubber boots in but take off the hose clamps!!! Keeping the clamps on will make this harder and mangle them.

2. Make sure you have the breather hose and clutch cable disconnected.

3. Go in with the carbs from the RIGHT. This is because the throttle cable perch as well as the idle adjustment are on the right side. It's just easier this way.

4. Come in low, with intake below the boots, then once you've wrestled the carbs over horizontally, tip them up into the engine side boots (harder). You can smoosh the airbox side boots on afterward (softer).
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Offline Bankerdanny

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Re: what's the secret to installing 550 carbs?
« Reply #13 on: July 29, 2019, 01:32:28 PM »
heat and lube.

In the summer I put the manifold boots out in the sun to get nice and warm then use a thin smear of lithium grease on the carb side. For the plenum side rubber you just need to fold it so the carbs slide past. We have a set of picks and hooks like this in my brother-in-law's garage: https://www.harborfreight.com/hand-tools/specialty-hand-tools/pick-and-hook-set-7-pc-69592.html that I use to get the plenum rubber on the carbs.

In the end there is no easy way and there is typically lots of swearing involved. I almost wept for joy when I discovered how easy it was to get at the 750 carbs last year.
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Online bryanj

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Re: what's the secret to installing 550 carbs?
« Reply #14 on: July 29, 2019, 02:58:25 PM »
No secret just BFI
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Offline ekpent

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Re: what's the secret to installing 550 carbs?
« Reply #15 on: July 31, 2019, 04:11:20 AM »
On the 500/550's +1 on unbolting and getting the airbox as far back as possible.  Heat,lube.removing outside airbox clamps and also holding your mouth just right while fighting it on. Good large pick and judicious use of certain words that children should not hear helps also !!  ;D
  Those o-rings under the metal manifolds might wanna be changed out also if its a keeper while its apart. I tried once but they were stuck tight and said F it and moved on.
« Last Edit: July 31, 2019, 04:15:44 AM by ekpent »