Jetting question

[Giggity]

I've been searching for over an hour but cannot find the answer. What jet sizes are needed if I am running EMGO pod filters with stock exhaust at 5000 ft. ? I have the early carbs ('79). I really want to get this thing running correctly.

[natemoen]

Here is a link to the jetting recommendations. You might go one size leaner to start with due to altitude.

http://www.xs11.com/forum/showthread.php?t=382

[petejw]

at 5000 ft u could try and leave it stock
and see how it runs, if its then running a bit lean
u could bump the main jets up by 2 sizes,

with those emgo filters just be aware they have
a inner lip that can restrict the air jets and cause
the bike to run like crap, some have added pvc pipe
at the back of the carb bell then attaching the air filter.

[tinman905]

You might need to lean out your idle jet screws a 1/4 to 1/2 turn . The higher the sea level the richer you carbs will be.

You are a bit high on altitude for stock setting but not by much. With your stock exhaust you might be okay at stock jetting .

Run it and check your plugs. Just make sure you sync your carbs if you make any changes to them .

[Giggity]

Thanks for the replies. So, according to the link I should only go up one size? (up 3 for pods, minus one after adding all increases and minus one for having stock exhaust) What about pilot jet size and needle clip setting?

I have a colortune but have not yet used it. Should I use that before making any jet changes?

I am able to ride the bike but it seems to pop thru the carbs a lot, hesitates when I hit the throttle and idles really high once it warms up. I just had the carbs apart and cleaned as I thought that was the problem prior.

[natemoen]

First off, if it idles high once its warmed up you need to turn the idle down.

Second, I would probably do the colortune with stock jets first. As I said before, fi one less than suggested, which would end up being stock getting anyways. I would use the colortune and get it as good as you can as is before changing any jets or needle positions.

[Giggity]

Forgot to mention the thing takes off like a scalded dog once it hits about 3000 rpm.

I have ridden it around the neighborhood without the filters on and it does the same, so that's not an issue.

I did have to drill out the tips on the fuel screws so I think colortuning will be the next thing before I take the carbs off again.

[tinman905]

Sounds like you need to sync your carbs. Reving high after it's warmed up is one sign they may need syncing.

[Giggity]

I did bench sync them after reassembly. I currently have a homemade sync tool I use on my boxer motor. Can I use that? Or must I have 4 tubes connected at once?

[tinman905]

Bench syncing is just to have the carbs close so the bike will run really. You are best to have a snyc guage that can give you a reading of all 4 carbs at the same time . One adjustment on one carb may change the adustment on another so it will be difficult to get them all the same

[DiverRay]

You CAN use the tool you made for the boxer, just need to do so in the proper order.
Sync carbs 1&2 first, then do 3&4. Then hook you tool up to 2&3 and get them synced. After, check 1&2, then 3&4 again, and finally recheck 2&3. This takes about twice as long as with a 4 position tool, but it will work. Remember, get them close, THEN adjust the idle screws per KEN'S method, (I think he wrote it), and check the sync one more time. At 5K feet, you may have to go up just one size on the main, but if it's already running well ABOVE 3K, probably not.

[skids]

The colortune is really not much good for mid to upper rpms. It is good for checking and making adjustments to idle and just off-idle rpms though. If you make adjustments with the pilot screws at say 3000 rpms, you will likely find the idle mixtures way off. The colortune will get the idle close, then you are better off coloring spark plugs for mains. Needle clips are usually better off left alone (78 and 78 model carbs). This is how I do it anyway...

[petejw]

under 3000rpm, is usually float levels and/or mixture
screws, if the bike runs well after 3000 rpm i wouldnt
worry about the main jets at this stage, what have u set ur
float heights at?
also with the early model carbs with the vent tubes it is
harder to get them to run as well under 3000rpm with pods, compared with having the airbox attached.