New Member from Denver

[petejw]

There are some small differences between the models,
ive got an 81 model so some1 with an earlier model will chime in.

Off hand, the carbs are different, but will interchange within the models,

the 79 had a mechanical advance as well as the vac advance.
1980 only had vac advance.

The heads are different, the 79 has smaller valves and a larger
intake valve gap. The intake cam is also different.

and i think the TCI is different, how does it run?

[XSBell]

It was parked 2-3 years ago and hasn't been started since. I've turned it over a couple of times and it sounds like it wants to. Needle and seat in carb #2 is not sealing or float level is off, gas is coming out when petcock open. I'm pull'n the carbs tonight and go thru them and throw in some new plugs before trying again.

[petejw]

just check your tci,
if its the earlier tci to suit the 79 the part no on it will be 2H7
i think the 80 model had a 4RO tci.
the tci is located under the seat.
if im wrong i hope someone will correct me.

If you have the early model carbs, the mixture screws are
visible on the front outside of the carb,
the later model carbs had the mixture screws set into a tunnel.

the float setting for the early carbs are 25.7mm
later carbs 23mm

hope this helps you.

[motoman]

Nice bike there! 4RO in 81 ONLY.

[petejw]

thanx motorman, wasnt sure.
so does that mean the 80 has a mech adv?

[XJOK2PLAY]

Falls under this...1980 XS1100LG 4H3-000101 New Yamaha Black.

Got luckey and found a manual at the library so I'm going to go grab it. Dying to know if all those lines are req, from the tank going to that small control valve then to the carbs. I would like to stream line things if possible.

Thanks again men.

You must be referring to the wad of hoses under the tank & around the carbs affectionately known as 'The Octopus'. Yes, that mess can be removed... but once removed, you always need to shut your petcocks off when you park it.

Should be a thread about it...one of the first things we got rid of when I got my bike and the guys helped me get things fixed up.... they knew exactly what it was, what it did, and what to do to get rid of it... but I didn't. One of the guys grabbed up this wad of hoses, jerked 'em loose from the bike, and slung them across the shop floor saying, "Get rid a that crap... don't need that B.S. anymore". Freaked me out! Cause I figured it originally served a purpose, and it had been a part of that machine for 26 years.... and there was NO WAY I'd ever figure out how it went back on.... and I wasn't too sure he knew how it went back on either! LOL

Fortunately, they'd been to this rodeo before... and it was ok... (once I got released from the ER for the coronary I almost had... LOL)

[CatatonicBug]

Welcome to the forum, Bell! As others have mentioned, you can download a manual (there are 2 different ones) from the link in my signature.

Quite a mixture of parts you have there! That red just seems to clash with those MNS gold wheels though!

What kind of experience do you have with bikes? These things are really powerful, and if you are new to bikes, an MSF course is a definite must. We've had way too many XSives go down in recent months... Protect yourself.

The Octy can be removed without too much trouble, but you loose the added safety feature of the vacuum valve in it. Just remember to turn your petcocks off when you dismount and you'll be ok. Read through ALL the Tech Tips (even the ones that you don't think you seen right now) before you start digging into things. There are tons of tips and tricks that have been recorded over the years on this site, and the best ones are found there.

Good luck, and keep us posted!

[XSBell]

Octopus is gone. I have messed with vacuume petcocks before but never seen anything quite like that. My other bikes have been converted to on or off, so I'm used to the drill. I was curious if any one ever just used one of the petcocks and tee'd it to service the 2 carb inlets. Carbs might starve for gas... not sure. Checked #'s on TCU and it's the older one. And lastly, there is a vacuume line going to the advance, but I think i saw somewhere that the '79 engine used both.

[CatatonicBug]

I was curious if any one ever just used one of the petcocks and tee'd it to service the 2 carb inlets. Carbs might starve for gas... not sure.

The problem with using only one petcock is not fuel starvation, it's the fact that the tank has a huge tunnel in the middle, splitting the fuel supply in half for most of the ride.

[XSBell]

Thanks for the input Catatonicbub. I was in the middle of posting and just saw your reply. I agree, it's look'n a bit like a mutt right now, it has my curiosity up now as to the exact history of the bike.

I'm 46 and been riding since I was in third grade. A lot of street racing when I was young and stupid, older and wiser now...not sure about the stupid part. We have three teenagers one that rides, so I try and set a good example. Nothing like the twist of the wrist though to put a smile on a guys face.

Very impressed with the site, Tech tips is very thorough.

Other bikes in the barn:
1978 KZ1000
1979 KZ650

[XSBell]

The problem with using only one petcock is not fuel starvation, it's the fact that the tank has a huge tunnel in the middle, splitting the fuel supply in half for most of the ride.

Gottcha, I new there must be a good reason. I will be cheching out your site soon.

[DenyP]

Congrats on your purchase, and welcome to the group!

Deny

[oseaghdha]

If it was me, I'd take those pipes off and store them.
They are as rare as rocking horse $hit.

[Fddlefoot]

Welcome

Sounds like you know more than me but have a 79 & 80 special up in arvada and would be glad to help or learn if you need anything just let me know

[XSBell]

If it was me, I'd take those pipes off and store them.
They are as rare as rocking horse $hit.

So what bikes were privey to the black pipes?