81std no top end - ignition unit??

[BA80]

Greg,

Have Clymer, and i think shop manual in pdf.
will pull cam cover and check cam shaft timing. And about a dozen other things.

You'll need to pull the left engine cover as well and when the cam timing marks are lined up the pointer should be pointing to TDC.

[RS Thornton]

evidence of earlier performance

TC
If you check the for sale thread you will find evidence of a succesful engine overhaul. Previous owner had bike performance documented by local law enforcement. So, looks like it is just a matter of going through all the checks until I get it sorted.

[TopCatGr58]

Hey again,

The Thread you provided was the craigslist one, which didn't show anything, you didn't provide the forum For Sale thread. Yes, even though you can't change the timing plate position, you can still check it with the timing light to show/verify that the TCI is advancing the timing with the rpm!

You didn't state if the carbs are correct for the bike, same year or not. As well as the jet sizes. Running out of steam at the upper rpms does hint towards lean, or too low float level? JAT!

T.C.

[motoman]

So shop is now a mess and I am no able to find timing light. Either I lent it out or it got displaced during the move. Not sure it matters though, according to the 81 supplement in the clymer manual you cannot adjust timing. Thought (and still do) that I finally had a turnkey xs, but will go through all the checks in chapter 3 of the clymer through the week. Really hoping it is bad ignition box.
Does not have carb problem feel, nor the bad pickup stutter/power loss. It feels a bit like when I had a 78e cent advance on an 80 special, no giddy up at higher rpm. Not sputter or popping just no oomph. Happens in all 5 gears so bike will get up to speed, but in a most boring fashion.
Wondering about the pickups, might swap over the set from the other 81 std and see what happens.
On positive side, it passed the TX safety yesterday.

Mixing components to get centifical timing unit in place IS the issue. Spring tension changes WERE make for the 80 model, and don't match cam overlap time between the two.

[RS Thornton]

http://www.xs11.com/forum/showthread.php?t=43722

This is the thread I thought I attached. Tried the third cdi, no joy there. Good nees us think that means all cdi are good, bad news is I have to look at averything else. Felt like good air flow through snorkle but dropped bottom of airbox and filter off but no improvement. Have a list of possibles from this thread and Gregs so will work my way through the 3; compression, spark and fuel and keep you posted.

Meanwhile the big bore project will have to sit. Got a neat front end set up; bandit triple with royal star forks.

[RS Thornton]

Tc
Bike is stock air box and carbs from what I can tell. Pulled them as bike was off at idle. Found sticky floats and one pilot was dirty. Idles well now. Actually runs lije a gl1000, so ok but not like an xs.

[motoman]

These bikes should take off at 5k, mine bogs out and will not go over 7k rpm. Feels like a 78e with centrigul advance issues, but the 81 does that in the magical black box. Tried a spare unit and same thing, so either both are bad or it is something else. Any other way the advance might not work besides bad igniter? Bike is new to me so do not know when this started, spare igniter is off a bike I bought but never ran so could be two bad units. But want to double check everything before I spend money on another one.
Going to check timing but doubt that is it, bike runs just fine in 1500 to 3500 rpm. Then is ok 3500 to 4500 but does not accelerate as fast as it should.

Disconnect vacuum advance at the lower plate. Hook a timing lite up going to #1 plug, Start up and lightly rev it up and let off throttle, ////electronic controlled mechanical advance euther works or it don't. Easy test my friend.

[RS Thornton]

Easy with a timing light.....
Should get to it this weekend when I either find mine or borrow one. Been two relocations since I last used it.

[BA80]

$19 at Harbor Freight.

[mro]

Good use for a set of cr%py carb boots

I really dislike having to do things over and then sometimes having to do it again... Carbs in particular, so I made this.




Shows actual fuel level in the bowls, plus if one leaks you don't have to pull em again and again.

[motoman]

Good use for a set of cr%py carb boots

I really dislike having to do things over and then sometimes having to do it again... Carbs in particular, so I made this.




Shows actual fuel level in the bowls, plus if one leaks you don't have to pull em again and again.

...........cept for that is SUPPOSED to be an idling fuel level. Float needle spring tensions for complte shut-off vary, so that is the way NOT to check fuel t levels.
what your showing as a short-cut does NOT work in the real world!

[RS Thornton]

Greg,
Looks like you win the trouble shooting contest. Last night I started the basic checks and found all 4 cyl had low compression, all at 90. Tonight pulled cover and cam timing is out, likely one tooth. Will reset tomorrow and recheck compression.

[BA80]

Greg,
Looks like you win the trouble shooting contest. Last night I started the basic checks and found all 4 cyl had low compression, all at 90. Tonight pulled cover and cam timing is out, likely one tooth. Will reset tomorrow and recheck compression.

Lets see a pic of the timing marks. Inquiring minds want to know.

[mro]

motoman

...........cept for that is SUPPOSED to be an idling fuel level. Float needle spring tensions for complte shut-off vary, so that is the way NOT to check fuel t levels.
what your showing as a short-cut does NOT work in the real world!

Would you enlighten me motorman?
How about a video of you adjust the fuel level while it's idling.
Could be that the factory manual is just wrong again?

[motoman]

motoman


Would you enlighten me motorman?
How about a video of you adjust the fuel level while it's idling.
Could be that the factory manual is just wrong again?

While idling, you have to 'hose' the carbs, if one has the later model carbs with the sidescrew bowl drain. If not the later model carbs, the Ford caliper bleeder screw fits in place of the large bowl plug. Adjusting fuel level while running..........surely you are joking with that one. Take measurments, write them down then pull carb assembly, remove bowls and make float adjustments accorfingly. This will also make you an expert at carb R/R.