Nothing above 4k rpm

[Adams77]

Hey guys

I'm a new XS owner. I picked up a nice 79 XS11 and almost everything works.......or at least it runs kind of.

First question

The bike will crank and idle but I have nothing above 4k sitting or riding. P/O gave me new carb boots (says the old ones have cracks hence the problem) normally a vacuum leak would affect idle and just off idle too wouldnt it?

Second question

Turn signals....I have to hold the button for them to operate, is this normal?



Cant wait to be a part of the XS11 community..........

[petejw]

hi adam,
welcome to the forum,
with regards to the engine running, sounds like it could
be in the ignition system, i think from memory the 79 is
similar to th 78 in that there is a mechanical advance and vac
advance, the mechanical advance could be sticking and needing
a bit of lube.
also check for broken pick up wires, if you do a quick search a heap
of info will come up

also at 4000rpm with the carbs the slide needle and emulsion tubes
come into play, but if the engine does it both whilst sitting stationary
and whilst riding, then id probably rule that out, as the slides wont lift
unless theres load on the engine.

with the blinkers it isnt normal to have to hold onto the switch,
the switch should return to the middle position, you might have to
pull it apart and have a look inside.

[Adams77]

I didnt even think about the mech advance. thanks I will look into that.

[old_chopper]

Are all four pipes hot? Does it have air filter(s) on it? Make sure the exhaust isn't plugged.

[Adams77]

All pipes are hot, filters in stock location.

Found something interesting, I will take pics soon. The choke is held on by a screen door hinge, no I am not making it up, a hinge.

Great execution of MacGyverism but a fail in my book. You pull the choke out and the hinge falls in to keep the plungers out, lift the hinge and viola the plungers go back in.

What else will I find?

[DGXSER]

Only time can tell what else you will find. POs can be very creative, although often mislead.

You may want to look at the carbs. It is more often the pilot circuit is gummed up than the mains at that higher RPM. But I know I had oen set of carbs where the bike sat for a loooong time, I had to DRIVE the emulsion tubes out (using a wooden dowel) and the gunk filling the gap between the emulsion tube and the carb wall was like sandy mud!!! Yours can;t be that bad and run I would think. But still, worth looking into those carbs.

Also, try the checks on the coils for resistance, and the TCI and pickup coils.

[CatatonicBug]

All pipes are hot, filters in stock location.

Found something interesting, I will take pics soon. The choke is held on by a screen door hinge, no I am not making it up, a hinge.

Great execution of MacGyverism but a fail in my book. You pull the choke out and the hinge falls in to keep the plungers out, lift the hinge and viola the plungers go back in.

What else will I find?

There is a spring that pushes the choke lever back in, but there are supposed to be a tiny ball and a spring under the choke shaft on the #1 and #4 carb that make 2 detents to allow full, 1/2, and closed positions. The balls are available (I have some), but the tiny springs are a bit tougher to locate. You may find that they are still in the holes where they belong though. IN reality, you only need 1 of the balls/springs to keep the detent working fine.

[RS Thornton]

The good news is that the XS11 is nearly bulletproof, so as long as it was not run without oil you should be able to fix it. I always suggest that new owners find a clymers or similar, between that book and this forum you should be set.

An orginal set of carb boots is going to look cracked, but that doesn't mean they go all the way through. Best test is to hit them with a shot of starting fluid when the bike is idling. If they are cracked through the bike will speed up when you do that. just make sure all the vacuum ports either have a cap or a good vacuum hose on them.

for the 4000 rpm limit one thing to check is that throttle cable is set up right. I did have one once with a goofy throttle cable that first 1/4 turn of the throttle was needed just to pick up all the slack.

good luck,
Scott