Alternative to Carb Caps?

[Teh_K]

So, we're doing a carb sync on the GF's bike and I notice that on carb #1 and #2, there is no cap over the little vacuum ports - instead, there are small pieces of rubber tubing (about 3 inches long) that stick out, and they're plugged with large plastic screws...

(Of course, carb #3 has a little cap on it, and carb #4 has the vacuum hose to the tank.)

I obviously need to take the little hoses off of #1 and #2 in order to sync them (extra length in hose = different readings when comparing to other carbs), but my question is:

Should I take off the little hoses on #1 and #2 and put back the standard caps? Or can I just leave the 3" capped hoses? Will the hoses somehow cause carb #1 and #2 to behave differently when all put back together? Her bike already had weird idle problems, which is why we're syncing in the 1st place.

I suspect the dealer we last went to put them there to ease the next carb syncing (since the caps on #1 and #2 are kinda hard to get to), but we don't go there anymore.

Anyways, thanks!

[Black_peter]

You can get little vacuum caps at AutoZone etc..
Not sure that a few inches of hose will throw off your readings..
But simpler is best..

[trinc]

if i was going to resync my kat again i'd build a little bracket and run a small length of hose to it. they are a b$tch to get off & on with the carbs in place. the pre-98 carbs are soooo much easier. vacuum is vacuum, the extra length is no big deal as long as it doesn't leak.

tim

[The CyberPoet]

Common solution (as suggested by BP):
Any auto parts store will carry a collection of them for $1 - $3. Go buy replacements and install them. Take the good one from carb #3 to match for size...
This is the best solution.

Cheers,
=-= The CyberPoet

[Teh_K]

Well, don't get me wrong, they DID make the sync easier 'cause I didn't have to pull the carbs out to get to the little caps - so, I'm almost thinking I should keep the little hoses there for next time. I'm more concerned on the effects of this.

In theory, what trinc said should be correct, but I don't want any ill effects of having these little tubes on #1 and #2.

Q1: Will anything bad happen if I leave the tubes there when all put back together?

Oh, another thing - when I was doing the sync, all the carbs were lined up at around 2K, but if you hold on the throttle (around 6K), the vacuum levels start to vary a lot and sometimes carb #1 lags a split second - Q2: Is this normal?

[The CyberPoet]

Q1: Will anything bad happen if I leave the tubes there when all put back together?

In theory, there should be no negative effect as long as they are truly air-tight. A hose bridging connectors on carbs one and two will also work, as long as it is air-tight.

Oh, another thing - when I was doing the sync, all the carbs were lined up at around 2K, but if you hold on the throttle (around 6K), the vacuum levels start to vary a lot and sometimes carb #1 lags a split second - Q2: Is this normal?

The lag is probably because of differences in timing on when the cylinder draws in it's fresh air charge (1 fires 180 degrees off of 2, etc). But if in doubt, swap the sync tool's lines between one and two and establish that it is the engine and not the tool itself having an issue.

Cheers,
=-= The CyberPoet