Broken Mixture Screw / Needles - Replacements ?

[catdna]

Hi All

Just returned from a nice holiday and my mechanic friend who was looking after my XS11 trike, informs me that all 4 mixture screw / needles in my carbs are broken off

Thanks to the tips section on here, I'm pretty sure they can be removed (fingers crossed) - so what I want to know is, where can I get replacements from (assuming they can be removed in the first place) ?

I'm not even sure what the correct name to search for is ('mixture screw / needle thingie' doesn't return any hits in ebay )

Cheers
Chris

[DiverRay]

As they are broken, I'll assume a '78 or '79 carb. You mechanic CAN just turn down the ends of the screws with a fine file and then emery cloth. Chuck the screw in a drill press, use the file to keep the taper, and finish with the emery cloth.
Second option would be new screws from mikesxs. com. I know he has a EU site, and all you need to do is order them for a 76 or 77 650. Just order 4 screws.
Good luck, and hope this helps!

[catdna]

As they are broken, I'll assume a '78 or '79 carb. You mechanic CAN just turn down the ends of the screws with a fine file and then emery cloth. Chuck the screw in a drill press, use the file to keep the taper, and finish with the emery cloth.
Second option would be new screws from mikesxs. com. I know he has a EU site, and all you need to do is order them for a 76 or 77 650. Just order 4 screws.
Good luck, and hope this helps!

Not sure of the age of the carbs - they aren't from the original bike that the engine came from so matching bits up is a bit tricky at times

I've sent him the link to the 'tip removal' tip - he's a very resourceful bloke so I'm sure he'll have no trouble getting them out. He's into reusing bits & bobs too (if you saw the trike in real life, you'd understand ), so hopefully he can fix them.

Looking on mikesxs site, I guess Part #48-5009 would be the one to go for (if he can't fix them) ?

Cheers
Chris

[DGXSER]

Are the mixture screws heads (part you put the screwdriver in) exposed at the front of the carbs? or are they down inside a tower?

If they are exposed they are the earlier model from 78 or 79. The 80 and 81 model carbs have the tower like this.

[fredintoon]

I've sent him the link to the 'tip removal' tip - he's a very resourceful bloke so I'm sure he'll have no trouble getting them out. He's into reusing bits & bobs too (if you saw the trike in real life, you'd understand ), so hopefully he can fix them.
Looking on mikesxs site, I guess Part #48-5009 would be the one to go for (if he can't fix them) ?
Cheers
Chris

Hi Chris,
sometimes those tiny broken off tips just won't come out with any of those tricks. Certainly the one in the middle carb of our XS750 (same carbs) didn't.
We very carefully drilled ours out in a drill press. The ideal diameter drill bit is 1mm (.039") but we had to use a 1/16" drill bit because that's the smallest the chuck would grip. You don't have to screw the needle as far out, is all.
I am not sanguine about successfully reshaping the ends of busted needles. For what they cost, buy new ones.

[catdna]

Thanks for all the replies guys - yep, the carbs must be from a 78/79 model as they're 'exposed' (then again, I'm in the UK and I think we're more forgiving with our emissions )

freedintoon - thanks for the info - I'll pass it on to my friend.

Cheers
Chris

[catdna]

Quick update -

My mate has managed to remove all 4 broken tips, but he's worried that he might have widened the holes the screws go into which could cause other issues - so now on the look out for another set of carbs :-(

(really wish I'd have seen that 'freezer' tip earlier !)

However......

... I've also just won an XS1100 on ebay ! - I can see the trike and bike swapping bits between them while I wait on spares to get both running

Will post pictures of the bike when I pick it up on Sunday / Monday

Cheers
Chris

[tarzan]

You should be able to use new screws.It will just be a little tougher to find that sweet spot where your mixture is right.If that is the only thing holding you back
I would try it.
Good luck getting it running.
Rick

[bikerphil]

Yep, I have a set of 79 carbs with the buggered up mixture screw holes and they run just fine. Tuning them will be more sensitive like tarzan said.

[catdna]

Thanks guys - I figured they'd be harder to tune, but that's not going to happen until next week now.

I do have a spare set of carbs that were originally on the trike, and I know that set also has at least 2 broken screws - gonna try the freezer trick over the weekend and see what happens (just need to wait for the Mrs to go out so she doesn't freak )

Cheers
Chris

[DGXSER]

Just put them in a grocery bag ("plastic or paper sir?") then she can't say a thing. Ok...she still can.

[catdna]

Just put them in a grocery bag ("plastic or paper sir?") then she can't say a thing. Ok...she still can.

Well, I finally picked up an XS1100 with just 2 wheels this time - had a very nice ride home, except for the clutch which kept slipping at any revs over 4-5000 rpm

Checked the cable when I got home and it was stretched to it's limit - have given it some free play now, but I'm not going out on the bike again for a few days - it's not taxed, and I was dodging police on the way home from buying the bike

Also, the carb rubbers are knackered - but the thing ticks over beautifully ! just as well I have some spares that I got with my XS trike.









So, for those interested, it's a 1979 XS1100 (F) - at least, according to the original owners manual I have here - only done 24000 miles, and 10 of those were in the last 2 years !

It's going to take a few shakedown runs to get her running properly again I guess (no complaints from me except for the slippy clutch and the cracked carb rubbers).

Now, a quick question - on my XS11 trike, it's easy to remove the carbs (no airbox, just pods and a tank which sits about 8 inches abover the engine :-)) - looking at the bike, I can see why so many people moan about the work involved to remove the carbs.

Anyone got any quick tips on carb removal so I can change the rubbers ?

Cheers
Chris

[bikerphil]

1. Take off seat, tank, side covers, and lower half of air box (4 wing nuts).
2. Remove the 3 bolts (10mm) that hold the upper air box to the frame. Do not remove any of the Phillips screws from the air box.
3. After loosening the 4 clamps, slide the air box towards the rear of the bike as far as possible.
4. Loosen the front carb boot clamps, tilt the carbs down and slide them back out of the boots. Detatch the throttle cable, vac line, etc.
5. I probably forgot to mention something, but you'll get it.

HTH

Congrats on the 2 wheel XS!

[DGXSER]

Phil nailed it pretty tight.

I would add that when you pull the top of the air box back, have a pick or something to slide into the bolt hole where the top 10mm bolt was to hold the air box back once the top bracket is behind the bolt hole.

Also, I find it easier to pull the back or air side of the carbs up above the intake boots...just what works for me really. And don't forget to pull the clutch cable from the bracket on no 4 carb, and the throttle cable out of the bracket that holds the outer cable as well as the cable end from the linkage.

ohhh...and having seen the orchestration it takes to re-assemble the air box if you pull those screws that hole the top braket in place, when they say not to pull those...LISTEN AND HEAD THE WORDS!!! PITA does not cover it!

And congrats on a really sweat lookin XS!!!!

[Ken Talbot]

Anyone got any quick tips on carb removal so I can change the rubbers ?

Hold off for a bit, until you check to see if you're actually getting a vacuum leak through the cracked rubbers. There's actually a metal layer inside the rubber walls that is pretty much leak-proof. Search the tips for how to check for leaks by waving an unlit propane torch around the rubbers while the engine is idling. If the rubbers are cracked bad enough to be leaking, the unburden propane will be sucked in, and you'll hear the engine speed up. If this does not cause the engine to speed up, the cracks are only cosmetic. That can be dressed up with black RTV silicone or spray-on rubber coating.