Some questions about carbs, exhaust, and jetting

I got my bike with pods on it. The bike seems to run well, but I am sure it would run better with the stock airbox. I am not concerned with power, I just want the bike to run as well as it can. Here are my questions.

First of all, I assume it is not, but how can I tell if this bike has been rejetted? I believe since the mains have a hex head on it then they have not. But, like I said, the bike seems to run ok.

I have TK carbs. I am debating whether it would be easier to jet the bike or buy a stock airbox. I have read that I may be able to get by by upsizing the mains, and adjusting the pilot jets. When I cleaned the carbs, I screwed the pilot jets in until they were snug (bottomed our) Is the adjustment as simple as just screwing the jets out a certain number of turns?

Will I be able to just buy main jets? Or is it likely that I will have to get the needle shim kit?

I like the look of the pods, but if the bike will run better and it will eliminate some tinkering i will scrap them. I was wondering however, if taping up a good portion of the pod will make the bike run with a better mixture.

Also, I have a 4 into 1 exhaust that is pretty beat up. If i replace the muffler with one like this:

www.dimecitycycles.com/vintage-cafe-race...uffler-80-45700.html

Will the exhaust flow be affected enough to require a rejet?

Using stock jetting with stock airbox is very straight forward compared to trying to tune the carbs to work well with pods throughout the rpm range. This is especially true with CV type carbs that KZ550's often have. Ed

The best way to know if the carbs have been rejetted is to compare the current jets to what would of been stock with the air box. From your sig it appears you have a 1980 550 with the TK round slide carbs. IIRC the 80 KZ550 came stock with the TK22 carbs with a 92 main jet and a 32 pilot jet. Some in the US have a needle that does not have adjustment slot, while others do. If your current mains are larger than a 92 I would say the carbs, at least the main have been rejetted.

You might what to check out this site home.comcast.net/~loudgpz/GPZweb/TK22mai...22mainPage.html[/url which belongs to member loudvx - it is all about the TK22 carbs.

Having said all of that if the bike is running well in its current state, why change it?

As gd4now said, the stock mains are 92, the pilots are 32 and the needles from the U.S. are not adjustable. If you get rebuild kits, you will get the stock mains and pilots, plus adjustable needles if you need them.

With pods, you definitely will want to rejet, but if it's warm out, and you let the bike fully warm up, the pods will work with enough to ride temporarily.

Some aftermarket exhausts will require a rejet, some can get by without it, albeit slightly leaner.

But if you just got the bike, and it runs, fine tuning the carbs is the really the last step. Please download all of the manual in my signature. You should start with a compression test, then valve clearance check (please read the valve train warning in my signature). Then check ignition timing for proper advance etc. Then check float levels. Then start fiddling with jetting.

If your exhaust is not stock, you will be playing around with some jetting, and the airbox will make it tougher, but not impossible. I usually set up my carbs so I don't have to take the carbs off to do jet changes or float changes.

There is plenty of TK-22 info on my site that gd4now pointed out.

Ok I read the warning, but I how do I actually relieve the tension on the cam chain? just rotate the 17mm bolt back and put the valve cover on? I am assuming that once I get it off it will be simple, I just want to make sure.

Also on an unrelated note, if I remove the ignition advancer to clean it, will i have to re-time the bike, or is it not connected to the timing marks?

The manuals in my signature willgive the details on advancer maintenance.

To relieve the tension, you remove the 17mm cap on the tensioner. Inside, there is a spring and cross-wedge. You should probably take the spring out so you don't lose it. The wedge can stay in as long as it is free to move.

If you are doing a lot of work, you may want to put the cap on loose so dirt doesn't get in, but obviously make sure it's all back together before running.

But you will probably want to read the section in the manuals for cam timing so you can get a better idea of how it all works.

If you remove the advancer on a points bike, it will probably need to be re-timed since the timing plate has to come off.

Is there a way to carefully clean and grease the advancer without removing it? I scrapped my busted tach a while ago and my light doesn't read engine speed. I guess its time to invest in a new light. I saw something about static timing in the manual, how accurate is that?

You can maybe oil it without removing the timing plate and advancer, but it's tricky through the timing plate window. If the advancer is rusty, you will want to take the rotor off the advancer mechanism and clean/grease it. For that, you will need to take the timing plate off.

The advancer doesn't actually have to come off the crank, but the timing plate has to come off to get access to the arms etc.

You don't really need to know the engine speed to set the timing plate. Just rev it up and the timing mark pointer should end up between the parallel lines on the advancer. That is what is most important. Then at idle, it will end up on the F marking, if everything is working right.

However, to check the advance curve precisely, you will need an external tach (or one on the timing light). I use this, which also has a dwell reading. Because it si for a car, you have to multiply some numbers to get the right reading.

www.autozone.com/autozone/accessories/Ac...entifier=122882_0_0_

ok. and the idle rpm isnt of the utmost importance either when timing?

Thanks.

yes, as long as the idle is low enough so the advancer does not start advancing. It should stay at the F mark.