Exhaust

[lancelot455]

Well i finally got the windshield and new exhaust put on the bike. But i noticed after a short ride(about 5 miles) that the header pipes are starting to turn blue. Number two seems quite bad. Stupid ? but what do i need to adjust to balance it out.
Here are some photo's of what it looks like now









Any help is appreciated.
By the way i have the old Mac 4-1 for sale now.

[petejw]

hi lancelot455,

the bike is looking good,
with regards to the blueing of the pipe, that
particular cylinder is probably running lean,
try turning out the mixture screw a little,
have u synced the carbs?
and are the float levels all the same?
also have a look at the spark plug and compare to the other plugs
if all the above are sweet, an incorrect valve gap could
also give a similar effect.

[James England]

Bluing is absolutely normal on single-skinned header pipes. The chrome reacts to heat. The OEM systems were usually double skinned and the outer chromed skin didn;t get hot enough to blue. My stainless headers went yellowy-gold within about 60 seconds. Ideally, if the headers are all made in the same way and of the same material (which, of course, they will be...) then you want the same level of 'blue-ness' on all of them. Yours look to be different and this means more heat is being generated on the cylinders where the headers have blue-ed, less on the other two. I'd tweak the mixture on those cylinders after examining all the plugs for colour differences.

If you look at most after-market exhausts fitted to working bikes, you'll see they always go blue, or yellow....

[lancelot455]

I have not synced or had the carbs apart at all. I did have the Yamarobber rebuild them last fall when i got the bike(charged me $800 to do the carbs and change fluids). I have never had a set of carbs apart or adjusted a set. I am new to working on bikes. But have worked on cars since i was 13 years old.

[petejw]

if u have some mechanical experience,
these bikes are quite easy to work on,
heres a link to wildkats write up of overhauling the carbs.

http://www.xs11.com/forum/showthread...ight=carbs+101

tho id try to unscrew the mixture screw a quarter/half turn and
see how that goes first.

syncing the carbs is also quite easy once u know how its done
u can either buy some vac guages/a carbtune or make ur own.

[lancelot455]

I was just going through the receipt from the Yamarobber and noticed that they changed 3 of the needle valve's part # 25G-14107-20 is that the right part # ?

[Yahman]

I was just going through the receipt from the Yamarobber and noticed that they changed 3 of the needle valve's part # 25G-14107-20 is that the right part # ?

Yes, that's the right number for the XJ1100. It's odd that they only replaced 3 of them, why not all 4?

Larry

[lancelot455]

I have no idea why they only changed 3 and there were not cheap either $55 each.

[WMarshy]

...I did have the Yamarobber rebuild them last fall when i got the bike(charged me $800 to do the carbs and change fluids).

At that price you could have bought 2 complete sets of carbs off ebay ready to run!

I have no idea why they only changed 3 and there were not cheap either $55 each.

Ouch... always hate to hear about people that got ripped off. A lot of people think the Yamaha dealers know what they are doing because they are an authorized Yamaha Mechanic. Truth be told, I bet half or more of the work done on your bike was by the shop hand who's making $12 an hour.

[lancelot455]

Where are the mixture screws located on these carbs. I'd like to adjust them but the manual didn't show me where they are.

[bikerphil]

Where are the mixture screws located on these carbs. I'd like to adjust them but the manual didn't show me where they are.

There might be a cap covering them which would need to be removed...they are on the front

[Ken Talbot]

Where are the mixture screws located on these carbs. I'd like to adjust them.

If you're going to start tinkering with the mixture screws, you should really look into getting a set of mercury sticks or vacuum gauges so you can get those carbs sync'd too, preferably before you start on the mixture screws. You will probably be able to buy the tool you need for less than the hour minimum shop rate you would be charged at a dealer.

[KA1J]

Well i finally got the windshield and new exhaust put on the bike.

<snip>

Nice looking bike. What exhaust do you have on there in the photos?

[lancelot455]

<snip>

Nice looking bike. What exhaust do you have on there in the photos?

It's a set of Jardine Spaghetti exhaust. You can't get them anymore.I was fortunate to get them from another member on here last fall.

[lancelot455]

If you're going to start tinkering with the mixture screws, you should really look into getting a set of mercury sticks or vacuum gauges so you can get those carbs sync'd too, preferably before you start on the mixture screws. You will probably be able to buy the tool you need for less than the hour minimum shop rate you would be charged at a dealer.

I do have a couple of friends here that have some gauges to sync the carbs. Where is a good point to start with the mixture screws? Turn them in all the way and then back them out how far?