carb synch

[Ebenezer]

Just got my carbtune in the mail and am going to attempt to do a synch. I've read a few threads on the "proper procedure" and just wondering if there is anything different on a 81 special that I need to know about. I got rid of my octy and also eliminated the prime via Steve's petcock mod. Any tips before I give this a shot?

[bikerphil]

Originally Posted by Ebenezer

Any tips before I give this a shot?

Make sure the engine is fully warmed up before syncing.

[motoman]

Make sure the engine is fully warmed up before syncing.
__________________
Have a good fan in front of motor while adjustments are made.

[latexeses]

You might want to run a electric fan on the engine to keep the engine from over heating while it is stationary.

[ccogswel]

You may have to hang it upside down. I had to on mine. Nice tool to have. Small and compact.

[Jeffintampa]

Mine has been serviced on the 2500 all three oils and filter, now just about due for anouther, I have never synced but bike runs good do I have to do it?

[cywelchjr]

I don't have the manual in front of me, but even if you don't pull anything apart or actually do carb work I believe IIRC that your supposed to do a carb sync every couple of years anyways, it's one of the period tuneup items on most multi carb bikes.

[Ebenezer]

Attempting to synch this thing. I got 1&2 synched. 3 is through the roof while 4 is at about the same as 1&2, relatively low on the carb tune. Do I really need to get them all as high as #3? The bike runs like crap when I get #4 at the same level as #3. It seems that either the gauge for #3 is whacked out, or something is messed up with my #3 carb. Any suggestions?

[XS1100 Newbie]

Make sure you are doing it in the right order. They should all read close to the same.

[Ebenezer]

I understand that you have to synch everything to #3 in the end. However, is it normal for #3 to be maxed out on the gauge? Or is this the sign of a bigger problem?

[MrOzz]

Proper sync is:

Sync 1 and 2 so they are equal to each other. (Sync screw is between carb bodies 1 and 2)

Sync 3 and 4 so they are equal to each other.(Sync screw is between carb bodies 3 and 4)

Then sync 1 and 2 to 3 and 4 using the sync screw between carb bodies 2 and 3.

When you sync 3 and 4, 1 and 2 might change. If they do, resync 1 and 2 then 3 and 4. Then you can sync 1 and 2 to 3 and 4.

The amount of vacuum does not mater to much as long as they are equal.

I am running pods with a dyno jet kit. The amount of vacuum on mine is 24 cmHg for all my carbs on my last sync.

Hope this helps you.

Ozz

[Ebenezer]

I totally understand the procedure. 1 to 2, 3 to 4, and then 1&2 to 3&4. I got that part. The problem is that 3 is maxed out on the gauge. When I synch 3 to 4 the bike barely runs because then they are both maxed out on the gauge. Then if I was to synch 1&2 to 3&4, everything is maxed out on the carbtune. I may be mistaken, but I am assuming that something else is amiss since #3 is maxed out from the beginning.

[Ebenezer]

Just to clarify, the #3 carb is constantly at 42 no matter what adjustments I make. I tried changing the hoses and no matter what hose or gauge I hook it up to, #3 reads 42. So it's not the gauge or the hose. The bike does not run if I go through the proper procedure and synch them all to that number. What causes it to be that high?

[CaptonZap]

I don't know under what conditions you are using the carb tune, but the following link has the directions on how to set it up and how to use it.

It may be that the restrictor for number three is missing, or any of a number of other things.
Wouldn't hurt to start over with the setup, and go from there. CZ



<http://home.comcast.net/~jrkengr2/html/using_carbtune_ii.html>

[Ebenezer]

Been there, done that. I tried different hoses to see if it was the restrictor. Doesn't matter what hose I use or what place I put it on the carbtune. However you look at it, the third carb shoots up to 42 on the carbtune. Is there no logical reason a carb should ever read that high?