Throtte Shaft Seals a necessity to change?

Makes sense. There's 3 idle holes on the carbs though, half cover the middle one.

Carb # 3 is the master. So first set that before setting others. What's the order if them again?

When I tried starting it last, both holes were uncovered at idle.

Will try this, see what difference it makes, and update.

 

For bench sync, I open til the middle hole on #3 is totally uncovered. (that way they are all open far enough that a different butterfly won't hold anything open or close too soon). Now ai adjust the remaining three to match. Doesn't matter what order. Once all match, I back the idle screw out til butterfly 3 covers half of the middle hole. Fine adjust the remaking three to match. Order doesn't matter. I snap them open a shut a few times, then check. Adjust if needed. install. Start up and do running sync.

My preferred order -

1. Balance 4 to 3
2. Balance 1 and 2
3. Balance 1/2 to 3/4

 

Priceless info, and so simple. It works too, better than a bodged running sync.

 

There is one idle hole (the one closest to the slide, also the one the the idle mixture screw controls), one transition hole (the middle one), and one enrichment hole (the one furthest from the slide, which also acts as a transition hole).

 

There you are, good explanation, and really, you should be able to see which order to adjust them - just work outwards from the master.

 

so update. I fixed the idle screw to where it should be at, i read somewhere before that you adjust it that you can just see a sliver under the butterfly valve, but obviously my 'sliver' was too much. Backed them all to where they cover most of the middle hole.

so now the bike idles at 3000 rpm, at a range which i can work with.

when i get my hands on a fire extinguisher i'm going to try a propane torch and see if the idle changes.

I'll even turn the idle more out, and see if that makes it better.

I also find after i start her a few times and she runs, when i leave it for a few minutes it ceases to start again. engine flooding? Not sure why that happens. it starts well cold, then after i turn it off, then try to start again it fails, no matter where the choke is.

When this bike gets up and running, i'm FedExing you all a case of beers

 

I don't do the 'sliver' or the 'card', or the 'paper clip'. I do the 'half of the hole' for the INITIAL SETTING and then Carbtune Pro from there to balance.

Have you BALANCED them yet? That will help a lot with the idle. Keep in mind that you WILL be adjusting the idle as you Carbtune, too, as part of the process.
Small turn,blip the throttle, let settle....small turn, blip the throttle, let settle.....repeat,repeat, adjust idle up or down depending on if it starts to get too low, or starts to race too much....l
Etc......l

 

The carbtune works the same as the other synch tools right? Like the gauges.. tests how much vacuum is going into each cylinder.

Don't I need the yics tool to properly balance the carbs. As it blocks off the airflow between the cylinders.

I'm going to try the propane torch today, if no noticable change in idle, I can rule out vacuum leaks. Then go from there.

Thanks again for your help.

 

Carb tune works like all the others........only better. Yes, you're basically balancing all the carbs to whatever one has the lowest vacuum. You're simply BALANCING them.

No, you DON'T NEED the YICS tool. I"ve never once used mine. Ever. When you're riding down the road, your passage isn't blocked, so whatever you balance with it blocked is going to be slightly different anyway. As I said before, unless you're going for picky amounts for racing, don't bother. These aren't high-tech micro-monitored engines anyway.

 

1. Carbtune is a brand of vacuum gauge.

2. The YICS tool is optional.

3. Propane doesn't always catch intermittant vacuum leaks (such as might be had with throttle shaft seals not always sealing). I prefer to use carb cleaner because it hangs around for a bit longer.

 

Ha, I always thought the yics tool was absolutely mandatory.

Unless I did any modifications (air pods, aftermarket exhaust) , should I worry about something like a colortune? I have the pilot screws set at 3 full turns out.
I will still check the plugs to see what color they become.

My main fuel jets stock are 120, but i have 122 jets installed, I did fit a K&N filter however. Pilot jet still stock at 40. Reading through Len's catalog, he suggests for every +3 main jet, you should increase pilot jet by +1. so i should be good?

 

You should be good, if not a tad rich. Most people end up at around 2 3/4 turns out. Keep looking at the plugs (the heat change on the ground strap, not so much the insulator color), and as you go leaner (if you find that you need to) listen for backfiring on deceleration (at which point you are too lean). Fuel economy is also a good indicator, but that will vary some with weather and road conditions. If you're getting less than 40MPG then she's very much too rich.

Having said all that, the priority is to get the idle down to no higher than 1500 RPM (and be able to kill the engine with the idle speed knob backed all the way out). If you can't do that, then there's still something not set up correctly.

 

Would this work for HSC33 carbs? Can you elaborate on the #11? What size is it and is it in inch or metric? Best, Nikolai

 

I got these. Have not tried them yet. I sent the dimensions l found on the forum to the supplier. They are the same dimensions l believe as the ones some XJ owners were ordering from the American supplier McMaster-Carr.

 

I used the X rings on my XJ700 carb throttle shafts. They work so far. They seem a loose fit into the carb body but so do the original C rings.

 

Good to know cheers.

 

I just stay with the throttleshaft seals from xj4ever

 

I would - without doubt - go for that option if I was located in the US. Shipping, import taxes etc just makes it too complicated and expensive.

 

Yes so would l if l lived in the USA. I am going to try the X rings because they are a good fit on the throttle shafts.