In need of assistance...

[JacobAndrew]

Hey everyone.. I can't seem to get my bike running right. I cleaned the carbs (several times) and put new coils on but it wont run right. It constantly backfires out the carbs and exhaust and lacks power under load. We have the carbs synced too. I had to drill out the air/fuel mixture screws so i'm sure that doesn't help. But I'm out of ideas and can't really afford to take it in to a shop. But I guess I'm looking for some direction, or if any experts on here live in SE MN and would be willing to help it would be geatly appreciated Thanks for any info.

[slow mo]

hi jacob

i try to tell all who will listen about checking pick-up coil wires especially if you are new ,, this is a very common reason why our xs11s run like crap ,, the test is easy and takes 5 minutes all other info about how to fix this can be found on this site ,,good luck ,,i hope i,m right ,,and ride safe ,,slow mo!

[WMarshy]

slow mo brings up a good point, you should check to see if your plug wires are arcing. There should be some posts about how to check it but in short, wait till its dusk/dark out and start the bike and look for any arcing. You can also take a squirt bottle and mist some water over/around the wires to see if it provokes any arcing. Any arcing sould be visible.

[DGXSER]

First of all, did it run right before since you have known or owned the bike? If yes, what did you change, change it back

Seriously, if it has never ran correct that you know of, then I would start with the big picture items. Three things have to be right, fuel, spark, and compression, and all at the same time. I'd start by checking that third one, compression. If you have some bent valves, or severely neglected valve gaps to where the valves are being held open, it will never run correct no matter what you do to the fuel and spark.

If that gives you good results, then move to timing. Hook up a timing light and see what it tells you.

Also, look at your spark plugs and see what they look like. If you have serious carb issues, the plugs will show it.

[SFerinTEXAS]

I would definitely rule out a jumped timing chain. The only way to do this is visually checking the cam dots and the timing pointer. A timing light will not tell if this is a problem.

start by checking that third one, compression. If you have some bent valves, or severely neglected valve gaps to where the valves are being held open, it will never run correct no matter what you do to the fuel and spark.

Valve clearance should always be checked before a good carb sync can be done anyway so while the valve cover is off that's when you can check the cam dots vs timing pointer.l

Not saying this is ( or 1 of) your problems but those are classic symptoms.

Don't neglect what slow mo said about the p/u wires.

I think I just heard the sound on a cherry trying to pop. Welcome to the long road of learning.

[fredintoon]

Hey everyone.. I can't seem to get my bike running right. I cleaned the carbs (several times) and put new coils on but it wont run right. It constantly backfires out the carbs and exhaust and lacks power under load. We have the carbs synced too. I had to drill out the air/fuel mixture screws so i'm sure that doesn't help. But I'm out of ideas and can't really afford to take it in to a shop. But I guess I'm looking for some direction, or if any experts on here live in SE MN and would be willing to help it would be geatly appreciated Thanks for any info.

Hi Jacob,
all good advice but the first thing to check (because it's a weird thing that those new to the XS11 would never think to check on and it's an easy fix) is the wires to the ignition pickups.
The vacuum advance moves the pickup plate back and forth as the engine revs which flexes the pickup wires so they can break inside the insulation. They look fine from the outside but they ain't. Take off the cover plate and gently pull on each wire. If the insulation stretches the conductor is broken.
There's a cheat sheet to be found under the search button that'll tell you how to fix it.

[windjammergump]

carb rebuild with no help

went thru my carbs ....started smoking from setting and backfiring...had a mechanic do a leak down test ...head and valves good rings not...alot of ppl according to him think carbs and it was valves or rings...if you do this and need rings and pistons i have .25 over rings but cant find pistons and wiseco is on and off for ordering and yamaha is discontinued period....dynoman is your choice to check with but i just spent 520.00 on wiseco kit..goodluck and stay in touch i am too far in as a newby to turn back now

[natemoen]

went thru my carbs ....started smoking from setting and backfiring...had a mechanic do a leak down test ...head and valves good rings not...alot of ppl according to him think carbs and it was valves or rings...if you do this and need rings and pistons i have .25 over rings but cant find pistons and wiseco is on and off for ordering and yamaha is discontinued period....dynoman is your choice to check with but i just spent 520.00 on wiseco kit..goodluck and stay in touch i am too far in as a newby to turn back now

you are never going to find first over pistons. All you need do is take the first over rings that you have to file them down so the ring gap is in spec. plenty of people have done it and it worked out fine for them.

[Cobia]

Check the integrity of your vacuum lines and that they are routed correctly. Also check the synch port caps on your intake manifolds.

[JacobAndrew]

Thanks!

Thanks everyone for the replies. ihm going to try checking the pickup coils when i get some time (we finally got some dry weather to get in the fields). Hopefully it works. I will let everyone know what i find out.Thanks again! Very much appreciated!

[greatnw]

I'm on the pickup coil wires or vacuum leaks. If the carb boots are nice and soft they can cause the vacuum leaks. Pick up wires and vacuum leaks are cheap to fix, carb boots will set you back a little more. Keep asking, these guys are amazing here!

[JacobAndrew]

Update

Ok, so I finally got some time to take a look at my bike and here is what I found out..
------Both of my pickup coil wires were broke, got them fixed and it still ran like crap
------My dad cleaned the carbs again, still didn't run right.
------Tried spraying starting fluid around the boots, no change..
------Went back later started it for about 15-20 seconds and felt the header, 1 and 4 were cold. Checked the plugs they were wet, but had spark. It was purple in color just like 2 and 3. They are new coils from MikeXS if that makes a difference.. I forgot to check the resistance of the coils, will have to do that tomorrow I guess......

[DGXSER]

I always like to start with the basics, so have you run a compression check?

The most likely issue is electrical. 1 and 4 are linked through the ignition circuits. And the most likely place to start is back at the pickup coils.

I would also try turning the fuel to prime and let the bike sit for about 3-5 minutes and see if any fuel comes out the air box. It is not likely that this is carb related, but if your floats are not sealing it can flood the cylinders.

[JacobAndrew]

I did a compression test a while ago, not quite sure what they were, but they were 120 and up. I put it on prime for a while and no fuel came out also..
Edit to add... I also check the pickup wires again, and couldn't find anything wrong with them...

[natemoen]

The biggest thing to look for compressionwise in new to you bikes is that the compression is reasonably even across the cylinders.