Newbie! With some questions of course.

[Presdo]

Hey everybody.

This should serve as an introduction and a question thread for me. I just bought my first XS400 today for a rockin deal. I'm 18 and graduate high school in may. I was really drawn to these bikes for some reason and some point in the near future I would like to start modifying it.

A little bit about the bike. 1980 XS400 with 3500 miles and a clean title. The paint is pretty clean and there isnt any dents Don't know how common that is with these bikes, but i'm pretty happy with the way it looks cosmetically. The PO said that the valves were re-lapped last summer and he rode it only a few times. Said he only ever got up into third gear for some odd reason. He said that he bought a battery last summer as well, but when I tested it, turned out to be dead. I bought the bike in non-running condition. He said that he thought that it needed new piston rings.. After it returned to my house, a friend and I fiddled with it for a few minutes and then hooked it up to a larger charged battery (all we had). It runs! BUT - here's where it begins to become confusing. It starts, but if you put any throttle onto it - it dies. If you shift into gear - it dies. The headlight is out for some reason but has a new bulb. Turn signals, brake lights and horn all work great. The battery is so dead that now it won't even start when it isn't being jumped. When I got to the PO's house he was charging it. He was actually a cop.. I will drain the old gas out tonight, I don't know if that is an issue though. (Is premium better for bikes?)

Here's a really bad picture of the bike. When it's nice out again this week i'll take some pics but my main priority is to get it running so I appreciate all the input I can get from you guys.

So what do you guys think is wrong with it? Why does throttle kill it? Why can't I shift into gear? I would love to get to riding this thing. Thank you guys!

 

[16VGTIDave]

Welcome Presdo! That is a clean looking bike! I'd suggest riding it for a while and getting it in top condition before you consider any modifications. If it is as nice as you've described, why not leave it stock? There are very few un-molested XS400's on the road these days.

I'd also suggest doing a search here about carb cleaning. 99% probability yours need to be cleaned thoroughly.

Did you have the kick stand down when you were shifting into gear? If so, try it with the kick stand up. Your bike may have a safety switch on the kick stand to prevent you from riding with it down.

 

[willem]

Nice looking bike!

Yea I'm with dave on this, clean your carbs (look on the forum here for how-to's and the manual), change the oil and buy a new battery. Check your brake pads front and back for wear.

Cleaning your carbs is most likely the problem with it not running well. Old fuel does deteriorate quite quickly and this clogs up your carbs. Also, when you've cleaned them, install a $3 inline fuel filter to prevent any gunk from the fuel tank to get into your carbs. Honestly, this will be the best 3$ you've ever spent.

Leave it stock for a while, or at least don't start hacking off stuff just jet. Get to know your bike before you take it to the butcher's

 

[Pork Chop]

G'day Presdo,

that bike looks like a great purchase. Such low milage, mine had done 65,000km which is like 50,000miles.

I agree with the other guys, clean those carbs a few times and then once more. Fresh high octane fuel, new battery, fresh oil, then see what happens. I would clean up the bike and ride it for a while before you do anything else with it.

 

[Greasey Fingers]

wow that looks sweet, good score! On premium fuel, someone I knew who ran a bike shop a few years back said one of the petrol companies (I forgot if it was bp or shell) boosted the octane in theyre 'high octane fuel' using sulphur. As a result, apparently he had heaps of bikes coming through with gummed up carbies. And he asked the owners what fuel they used and all of them were using the high octance from the same company. I wish I remembered exactly which company. But I don't bother using the high octane in any of my bikes anyway because its a rip off.

 

[Scorpio1963]

Welcome to the site with your nice xs.Run some seafoam through the gas,check your plugs.Take the petcock out of the tank make sure the screen inside the tank isnt clogged up.Take your airbox tubes off spray some carb cleaner in there.You should start seeing some improvments.Take your stator cover off and look and see if its all rusted.Maybe a good cleaning in there will help with keeping the battery charged.Good luck

 

[Lou Ranger]

... said one of the petrol companies (I forgot if it was bp or shell) boosted the octane in theyre 'high octane fuel' using sulphur. As a result, apparently he had heaps of bikes coming through with gummed up carbies...

Fuel is different in every country so you need to be careful. In Canada we can still buy SOME premium fuels without any added ethanol. Shell here makes a virtue out of its 91 octane NOT having any ethanol - they want all the business from Ferrari/Porche/Lambo etc. owners worldwide and commit to it.

Since ethanol is a really cheap way to boost octane ratings, it is likely that the company that messed up all the bikes put in more than 10%. Not really a problem with modern car engines but pretty deadly for old cars and bikes, especially if you take longer than a couple of weeks to go through a tank. It can separate from the gas. Once separated, the gas portion now has a lower octane rating and the engine runs like crap. And if it sucks the separated ethanol, then the carbs can get messed up. Riding every day certainly is one way to prevent the problem.

Some people around here, if they aren't going to ride again for a week or more and are using regular gas, will add stabilizer or Seafoam to what's left in their tank at the end of a ride. Just because they are paranoid doesn't mean that something isn't trying to gum up their carbs!

http://www.xs400.com/forum/showthread.php?t=10094
​

 

[Pork Chop]

wow that looks sweet, good score! On premium fuel, someone I knew who ran a bike shop a few years back said one of the petrol companies (I forgot if it was bp or shell) boosted the octane in theyre 'high octane fuel' using sulphur. As a result, apparently he had heaps of bikes coming through with gummed up carbies. And he asked the owners what fuel they used and all of them were using the high octance from the same company. I wish I remembered exactly which company. But I don't bother using the high octane in any of my bikes anyway because its a rip off.

Hi Greasey,

I was referring to higher octane US fuel. I understand that they consider 91RON as high.

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[Presdo]

Hey guys!

I got the sweet thing running! I gave it a quick simple wash on the outside and haven't even gone inside to clean the carbs or anything else. I tested negative or spark on one side and decent on the other so I replaced them. I got a new battery and charged it up. (Ive never had to pour the acid into a battery before, but it was a pretty good experience. I drained the fuel out and cleaned the tank out the bed I could, then filled it with ethanol free fuel I think it was? I could be wrong but a station near my house is selling something like it. The thing was so fun that I rode it around for a half hour and didn't realize how long I was out I'm lovin it.

I also went to the the DMV today and got my money taken to put a little M on my liscense card. Woo-hoo!

Anyway- check a pic.

 

[willem]

congratz!

I think we all recommend you to clean the carbs still anyways, it'll just make it a lot more reliable. But great that it works man, its looking good too

 

[Pork Chop]

Nice mate.

She sure is purdy after you cleaned her up - I wouldn't change a thing. Just ride and ride and ride some more.

Might be a good idea to get some new tires just to be on the safe side.

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[XSLeo]

If you look at the fuel requirements for the bike. I found the placard on my 81 XS650 inside one of the frame sidecovers. It said to run regular leaded, research octane 91 minimum. I have run todays regular in it. It pings a bit. 89 and 91 are better but the 93 doesn't ping. I use 93 because most stations around me only have 87, 89 and 93.
I have recently found several stations about 35 miles away that sell nonethanol fuels. Some have all grades others just 91. It runs well in my bikes.
In the Harley and the two XS's but the Honda CM400E runs fine on 87.
Greasey fingers. Have you tried the mid or huigh octane fuels in your bike. Try a few tank fuls of each to see how it runs as well as the fuel milage. The octane can and will have an effect on both.
Leo

 

[MrStubb]

Hey Hi Glad to meet ya. Just thought I'd add my 2 cents worth. Looks like you've hit the jack pot Presdo. With such low mileage I'd bet most of us are jealous. (I am) I can't stress enough that a good carb cleaning would do you wonders and it will give you some experience. You should use a little fuel stabilizer in each tank full to help with the ethanol problem our bikes suffer from. You'd do well to get a good repair manual for it as well. I think I'd keep it stock for a while so you can get used to the experience. After rideing it this summer possibly you'd have some idea's of what you want to modify on it. Then thru the winter go for it as money allows.

 

[mikegeeee]

Mine is totally stock... high octane... and lovin it!!:

 

[Scorpio1963]

Very nice bike looks fabilous.If your lucky enough to have a place near you that sells ethanol free gas keep using it.I absolutly hate this ethanol crap.I have an older veichle to drive also its causing me nothing but headaches.Our wonderful government is shoving it down our nozzles so we have to buy newer cars.If Im not mistaken you can buy mtbe additives which help with ethanol and the boost the octaine

 

[Presdo]

Okay where to start. After I got home from school today I took the carb off the bike and cleaned them. I checked my air filters which also look like they're in good shape. I then took the bike for a short ride in my neighborhood (very hilly I must add). Before I went on the ride I let it warm up on full choke for a few mins then took off on a ride. I took the choke off and the bike wouldn't Idle or start on no choke. So I rode with choke on. (Really bad thing due to running rich?) anyway, I would try to get into the higher rev range of the bike and there would just be a loss of power. Kinda like just a flat spot in the range. So I was just going to finish the loop then get home to figure out what is going on right? Well at the bottom of the biggest hill around, my bike shuts off. I was disappointed. I started it and it backfired really loud. (cOol.) Then I was starting up the hill and it died. I pushed it up and back home. It sucked. Anyway, now it won't start. WHY ???? I have spark and I have fuel. I also don't have a compression tester but I new to get one to check.

So two big questions - 1. Why is there a loss of power in the higher rev range?
2. Why won't it start?

Can't wait to see some responses. You guys are great about that.

 

[willem]

both 1 and 2 sound like carb problems. Did you probe through all the passages with very fine wire? And how's your idle mixture screw, how far out is it?

And how are your spark plugs looking? White and blistered or black and sooty? First is too lean, second too rich.

Often it will start again after 15-30 minutes, in all likeliness you drowned the engine in fuel when riding with the choke on. Have had my fair share of drowning as well. But if the carbs are still dirty, it's not going to run well.

good luck!

 

[Presdo]

Ok.

I tried to start it this morning and it wouldn't start still. Should I just take the caves off again and clean them? Where is the idle screw? (Sorry I'm so new to this ) and one last thing which setting should the petcock be on?

Thanks a ton.

 

[Scorpio1963]

Somewhat off topic but since mentioned about sulfur being used in gasoline I live close to a refinery.They sent notices to near by residents that they are reducing the amount of sulfur used in the refining process.Lou Ranger probaly knows what refinery Im talking about.We used to smell the stench of sulfer burning in the air all the time.Its alot better now.

 

[Lou Ranger]

Somewhat off topic but since mentioned about sulfur being used in gasoline I live close to a refinery.They sent notices to near by residents that they are reducing the amount of sulfur used in the refining process.Lou Ranger probaly knows what refinery Im talking about.We used to smell the stench of sulfer burning in the air all the time.Its alot better now.

I know the EPA there, and EnviroCan here, have mandated low suphur diesel fuel. Up until now, only VW brought small diesels over in cars because of the crappy diesel fuel in N. America.
Over the last few years, they brought over all kinds of giant tanks and equipment from Germany to refine low-sulphur diesel. The companies that have diesel pumps at their small vehicle stations are now supplying the low-sulphur diesel.
Don't know if the stations set up to fuel large rigs only are grandfathered in terms being allowed to sell the old dirty crap.