midrange power

[imcgyver]

Hello, I got my 1980 XS11 running again, first time riding a XS11, It has a 4 to 1 Supertrapp, stock airbox and carbs have 45 pilots and 125 main jets, my issue: when cruising at 2k- 2500 rpm I have no pick up power unless I down shift and get the rpm above 3K, is there a chance I need to put back the 42.5 pilots or 120 mains or both? or is that how all 1100 act? I have power above 5k rpm will take on highway later. I have A 1981 XS650 Special all stock and it has good pickup at 2k and up.
Thank you for your time and response.
Ron

[motoman]

Bettin' your a bit rich in the pilot circuit. Still havin' the stock airbox(which IS a good thing), may be a step too many with the mains too, JAT.

[imcgyver]

That would put me back to stock 42.5 pilot and 120 main jets, I thought that the pipes would need something bigger in jet size? If stock is the way to go I will put all stck jets back in. I am at 5400 feet altitude, if that helps any.
Thank you for your time and response.
Ron

[natemoen]

That is the problem with 4-1 exhausts, you end up losing the lower end.

['OlGuiltyBoy]

I got a question ..... Not to Jack your thread, maybe you can help too, but I plan on running my headers only (took the mufflers off as they were all rusted and f-ed up). I'm going to do an old school trick they did back in the day with drag pipes, I'm going to stuff some copper reducers as far back as I can into the pipe and then an inch from the end of the headers I'm going to attach some 1 inch thumb screws to kind of "block" the outlet. Creates back pressure. What sort of jet kit should I put in my carbs???

[natemoen]

I got a question ..... Not to Jack your thread, maybe you can help too, but I plan on running my headers only (took the mufflers off as they were all rusted and f-ed up). I'm going to do an old school trick they did back in the day with drag pipes, I'm going to stuff some copper reducers as far back as I can into the pipe and then an inch from the end of the headers I'm going to attach some 1 inch thumb screws to kind of "block" the outlet. Creates back pressure. What sort of jet kit should I put in my carbs???

You would have to richer it up some but no one can tell you, it is a guess and test game with carb tuning. Start out with a couple sizes larger and see what your plugs tell you and then adjust according to what your plugs say.

['OlGuiltyBoy]

You would have to richer it up some but no one can tell you, it is a guess and test game with carb tuning. Start out with a couple sizes larger and see what your plugs tell you and then adjust according to what your plugs say.

Colortune?

[ManagerMike]

Hello, I got my 1980 XS11 running again, first time riding a XS11, It has a 4 to 1 Supertrapp, stock airbox and carbs have 45 pilots and 125 main jets, my issue: when cruising at 2k- 2500 rpm I have no pick up power unless I down shift and get the rpm above 3K, is there a chance I need to put back the 42.5 pilots or 120 mains or both? or is that how all 1100 act? I have power above 5k rpm will take on highway later. I have A 1981 XS650 Special all stock and it has good pickup at 2k and up.
Thank you for your time and response.
Ron

Not uncommon at all, the powerband on these beasts just gets started at 3 grand, gets wide-eyed about 5g's, then peaks at about 8. Aftermarket exhaust (good luck finding OEM) pushes the power a bit further up the scale.

[natemoen]

Colortune?

Only for idle range and no higher.

['OlGuiltyBoy]

Only for idle range and no higher.

So what do I tune with to match my plugs?? How do I adjust according to my plugs??

[natemoen]

So what do I tune with to match my plugs?? How do I adjust according to my plugs??

you drive the bike,remove your plugs and look at them. If they look lean increase jet size, of they look rich decreass jet size.

You can also do plug chops, hold the rpms up high for a bit and then hit the kill switch before letting off the throttle. Pull off to the side of the road and remove the plugs and read them the same way.

[skids]

I would try coloring a new set of plugs after the engine and oil are hot. No sense warming the bike with the new set. Then run the bike at say 2500 rpms steady for about 5 minutes while you ride it. Then, pull over and check them. Take a spare plug or two in case you foul one. Take leather work gloves and the wrench.

['OlGuiltyBoy]

I can build the leaning tower of pizza, but if lean what color, if rich what color??

This is my first carb bike - I'm a crotch rocket guy. I am remembering blue on spark plugs.....which is that?

[DiverRay]

You are probably rich on the "low end", so I would go back to the stock pilot jet, and leave the main jet alone. Usually you go up three mains and one pilot. To adjust once you are close, you will be turning the idle screws on the front of the carbs. My guess is about two turns out with the 42.5 pilots should be good.
The plugs should be a light tan color, and black is rich, white is lean. Hope this helps!

['OlGuiltyBoy]

You are probably rich on the "low end", so I would go back to the stock pilot jet, and leave the main jet alone. Usually you go up three mains and one pilot. To adjust once you are close, you will be turning the idle screws on the front of the carbs. My guess is about two turns out with the 42.5 pilots should be good.
The plugs should be a light tan color, and black is rich, white is lean. Hope this helps!

I'll try it although I don't know what the stock jet is
This isn't my bike. I don't want to have to take it to a shop... appreciate the help