Half of engine not firing

[Ehdrian]

Hello!

I'm in the process of purchacing an 81 1100 Midnight Special. I have limited experience fixing motorcycle engines, but I think the problems this bike has are simple to fix.

The previous owner took very good care of the bike and stored it in his basement... but the current owner left the bike outside under a roof, with no walls all winter. During this time, the pipes were removed - so although no rain had landed anywhere on the bike, there was very high humidity. (Live on an island where only 4 weeks of snow in winter - the rest is rainfall)

The body and engine look mint.

Looking from the back of the bike the two right cylinders do not fire. All four plugs have spark. The current ownder has done almost nothing to correct the problem and wants to sell it.

I told him that as long as there is no rust in the engine, I will buy it.

I assume its two gunked up carbs, possibly all four have some gunk.... Could this be a bigger issue? If it might be expensive fix I do not want the bike. However, if all I have to do is remove and clean the carbs or change a couple gaskets, I will buy the bike.

All info/advice appriciated!!
Adrian

[latexeses]

If the price is right and/or you like the bike........

MNS's are not to common. I you have one in good physical shape the effort to get it back in shape would probably be worth the effort. These bikes really are a hands-on proposition. Sweat equity is a good way to put it.

If the bike has set for an extended period the carbs would be a good bet.

There are a ton of people here who have a lot more experience with this than I.

Oh, by the way welcome!

[blue giant]

Hi Adrian,
welcome to the board.

Looking from the back of the bike carb 1 is the very left carb and carb 4 is on the very right with 2 and 3 in between. Cylinders 1 and 4 are fired by 1 ignition coil and 2 and 3 by a second. Carbs 1 and 2 are fed fuel by the left side petcock and 3 and from the right side petcock. There is also a vacuum controlled fuel valve (octopus) that allows fuel to flow from to the carbs when the engine is running and creating vacuum. You will definitely want to pull the carbs and clean them as well as the octopus. Make sure the battery is fully charged and maybe try a fresh set of properly gapped spark plugs. All other regular maintenance items can be found on the main forum page under maintenance.

Good luck with the bike!

Paul

[Ehdrian]

I love the look and rarity of this bike :-) The price is $2500 CAN ($2230 USD). The current owner claims the bike ran perfectly last summer. After sitting for 6-8 months in high humidity with the pipes off, the two cylinders did not fire.

This is very tempting to buy! Based on a carb clean etc... not as tempting if I need to start changing valves. :-)

EDIT: Thanks paul! You make me want to start tinkering and I haven't even picked up the bike yet! lol

[tarzan]

Welcome,
It sounds like possibly carbs to me too.The two cylinders on the right are fed fuel from one tee.The same on the other side.
If you are looking for a trouble free bike ,that wont need a little tinkering this probably isnt it.But if you have a little patience and time then you will like it.
These are great bikes with good power.But they are 30 year old bikes and when they sit for extended periods if time ,like any other old bike,they develope
problems.So most guys end up spending some time at first sorting things out.
I am not trying to disuade you from buying the bike ,it just sounds like to me you may not want to fuss with it much.
Rude safe. Rick

[DiverRay]

The price is $2500 CAN ($2230 USD).

I paid $1,200 US for a RUNNING Midnight Special last August. $2500 CAN is too much money for a NON RUNNING bike, IMHO. My bike needed tires, and I've since put in new plugs, and adjusted the valves. That, and oil changes are ALL it needed. I would NOT go over $1500 CAN for ANY reason, and I'd probably stop at about $1200, just because of the poor storage.
Good luck, and let us know what you do get!

[TopCatGr58]

Hate to be the harbinger of possible bad news, BUT, sitting out side with NO EXHAUST PIPES and if the engine was not properly prepped for storage, like dousing the innards of the cylinders in oil, then there is a good chance that one or more cylinders would have been sitting with the exhaust valve partially open, allowing moist RUST causing air to get into the engine and cause rusting of the cylinders involved!

Don't know if you would be able to do a compression check on it? If so, and if they were very similar across all cylinders, then there's a good chance that the cylinders didn't get too rusty, and it may just need a good carb cleaning and such. But if the comps are considerably dissimilar, then I would be very leary about putting that kind of $$ down for it!?

Why in the world did he store it without the pipes on it?? Does it still have the exhaust pipes, and are they in good condition?
T.C.

[tarzan]

I didnt notice the price before.That would definitely be a deal breker on this one for me.
For $2500 you can get an awful nice bike that runs and looks good already.

[CatatonicBug]

I didnt notice the price before.That would definitely be a deal breker on this one for me.
For $2500 you can get an awful nice bike that runs and looks good already.

Yeah... Sounds like a really nice bike, but that really is too high for a questionable bike. Mine was in similar shape when I got it for $500US, and I've put about $300US into it just in parts and rebuild kits. There have been a few REALLY nice bikes available for sale on this forum in recent weeks for a lot less than $2500. However, it IS a MNS, and they are rare, so if you like it, and have the cash to spare, go for it. However, I would try really hard to talk the price down.

[tw1980]

Sounds a little pricey to me for a non running bike.Also if the carbs are the only problem that's no big deal,but I also think what Top Cat talked about is a legitimate concern.

[Ken Talbot]

So, which Island are you on?

I picked up a MNS from "an Island" just off of Vancouver. It was in running condition, barely, and needed a lot of restoration work. IIRC, I paid about CDN$1200 for that one. After a fair bit of work, it turned out pretty nice, at least, I think so.

The two dead cylinders basically come down to a fuel supply issue, and may be pretty easy to resolve.

The carbs are going to need to be done anyways and you'll be able to do that yourself if you follow the tech tips and ask questions if you get stuck. You'll also probably need to work on the brakes, replace the battery, and may need to replace one or both tires. You could try using all of this, and a hint of speculation that second gear may be flakey, to try to get the asking price down a bit. Or, depending on your negotiation skill, a lot!

[Ehdrian]

Big Thank You

Thank you to everyone!

I haggled down to $2000.

Here's what I'll get:

1981 XS 1100 Midnight Special
27,000 km (16,777 Miles) on OD
No visible oil on engine or tranny
One scratch on body (panel that says "Midnight Special")
Some pitting on front forks (not the shock, but the shock cover)
New rear tire
Saddle bags
Windshield
Crash Guards
Sissy Bar (tall back rest w/cusion)
Original black chrome pipes
Working battery

I pick it up on Monday or Tuesday. :-)

[tarzan]

Congrats on the purchase.I hope it is an easy revival.
BTW,you may want to check that tire for a manufacture date.If it is an old (new) tire it can be kinda dangerous.Age makes em slippery.It is generally not recommended to run a motorcycle tire that is more than 5 years old.

[Ehdrian]

Thanks tarzan. The rear wheel is 'last year new', but the front will need to be changed after this season for sure.

I took the carbs out and cleaned them out nicely. One of them was clogged.

Removed the valves from the gas tank and cleaned them and the fuel filter as well - one of them was siezed up pretty good, but I was able to loosen it up without wrecking the seal.

I was a little over zealous and removed the bolts from the top of the air box and ended up spending about an hour today trying to reassemble the stupid thing. All of the electrical seems to be in great working order so far. I also broke a bolt holding the seat in place.... righty tighty, lefty loosey LOL. Not sure what I was thinking.

It appears she might fire up tomorrow evening... pray for her - her name is 'Black Betty'.

Cheers!

[blue giant]

Way to go!

You soon be an XS1100 expert like the rest of us!



Paul