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drewpy
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Posts posted by drewpy
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hi the clutch cable is at the right lengh i have put a screwdriver in were the little piston that comes out when i pull on the clutch and it comes out about a inch but when i put it all bact together it does not do anything i am wondering if it could be the springs as when i first took it apart the plate was not in the groves and the person who put the new clutch plates in did not see what he done and compressed the springs to much i have ordered new springs
the springs should measure 34.6mm free length. if they measure 1mm less than this, then they should be replaced.
Is the mushroom head on the end of the rod?
check for warped plates using a sheet of glass
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From what I've read over the last day I've learned that pilot jets control idle, correct? Will unblocking also help with the slow dropping rpm's, or could that be symptomatic of another issue?
Also, will any small fuel filter do the job?
Thanks again!
yep they control idle to 4 - 41/2 K revs. my bike used to rev on idle which means too lean. just richen up on the pilot screw.(after you have unblocked it)
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I can see the light if I take out the mix screw and look down the screw hole to where the pin goes, makes sense to me to see light thru there.
The drilled ports - since the bike sat for a long time (a couple of years), could they be filled with varnish? maybe a good soak in carb cleaner?
just get them ultrasonically cleaned, you can buy cheap ones, but big enough for your carb and they also clean your dentures!!!
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i am redoing a yamaha xs400 1980 the problum i have is the clutch does not in gage when the the cluch handley is pulled in to change gear i have renewed the clutch plates and still does it does any one have any ideas what else it could be thanks les
I suspect the ball bearing at the end of the pushrod is missing
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I've got the same problem but oddly only with the headlight. I've got an '80 xs400sg, and the wiring diagrams all suck in one respect, they don't show what happens within the relay. I kind of suspect that somethings wrong with the relay in my case. Maybe you've got the same problem?
UK bikes don't have relays. the 4th wire feeds the main beam pass switch. I had to solder an extra wire from the ignition switch live to the pass switch on the left side and back to the headlamp main beam.
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Both the plugs and wires are solid. I'm assuming that the points are fine, though I haven't checked them closely.
Is there a chance that the points could go from perfect to shitty overnight? I assumed that wouldn't be the case and therefore have focused my attention on the carbs. perhaps I'm wrong?
its your pilot jet, this is the smallest drillings in the carbs and will clog up first. You also need to fit a fuel filter as your tank will have rust particles from gas stations and in the tank itself.
Try some of the proprietry carb cleaner you put in the tank and see if it unblocks. You could also open the screw another 1/2 turn and see what happens.
mine always runs the roughest at 4k revs. this is the point where the main jet starts to take over from the pilot system. Just age and 30 year old technology really.
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Thanks for the info, I'll pull the carbs back off and check. I've never used a screwdriver to tighten them, could it break off by finger tightening? And again, will tightening the mixture screw richen the mix or lean it?
n8
If youv'e had the bike from brand new and you can say you have never had a screw driver on the pilot, you can eliminate that then.
if you have the carbs off, take out the pilot screw and feel under neath for a little "pin" if its there its snapped off!!
Its an air screw, in for rich out for lean.
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To add to the above, I've been fiddling with the mixture screw for what seems like hours, and it doesn't seem to make much difference how I adjust it. In fact, I can completely remove it and the bike keeps running with a slight increase in RPMs. I can bottom it out and it keeps running about the same as 1 or 2 turns backed out from the bottom. I might add it runs very rich, and can foul the spark plugs in only a couple of miles.
n8
A common problem was hamfisted peeps overtightening the mixture screw in, then the fine brass tip snaps off in the carb body prventing any change in the low speed mixture.
my carb had both of these and got an engineering friend to "push" them through. It opened up the hole slightly but I just screw in the new screw more.
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Not so sure about that. You must have the points somewhere close first, otherwise it will affect the timing too much.
all the points do, is pass 12v to the coils for the appropriate amount of time (dwell).
I did say do your timing first, assumming that the points gap was already initially set (which they are) then reset them after the timing
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Thanks for the quick reply. The first order of business will be replacing the chain and rear sprocket (the front looked excellent). I've got my hands on a 39 tooth. As the original was a 37, I hope the jump doesn't alter the setup too much. Any thoughts on this change?
I would try it as you will get better acceleration. I had a similar setup and i was great. fuel consumption was worse and you tended to race other bikes/cars up to 80mph, so engine life would be shorter.
I now run 1 tooth over just to tame my red mist
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Hi I have replaced the points and the capacitor, I now have a spark at both points, however my next problem is timing, the bike has not run since may07, and I am having to time the engine manually.Every thing is fine with the points gapped but when I loosen up the back plate to time the opening of the points by turning the back plate they do not close, how loose should the back plate be when timing the spark. Help
do the timing first, then reset your points. invest in a Xenon strobe £20 off ebay.
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I recently purchased a '78 400 2e with only 8200 miles on it. This is my first bike and I would like to learn to perform maintenance on it myself. I am mechanically inclined and have a history as a bicycle mechanic, so things like swingarms/suspension/chains etc. come easily to me. When it comes to clutches and engines, anything other that simple repairs require SOLID photographs and concisely explained directions. The bike came with the original xs360/400 manual, but its zeroxed photos and badly edited content leave me a little confused. I've found both Clymer and Haynes manuals, but wondered if either one has a better reputation. Both are online, leaving me unable to check them out.
Jeff...
I'd also get a parts book, as this illustrates all the parts and you can phone suppliers with parts numbers.
I have haynes, Clymer and Yamaha manuals which differ in their presentation. I would say Yamaha manual to have the most information with torque settings and diagnostics etc
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I have a 1977 Yamaha xs 360. If it sits in the garage for about a week I can hop on it and go like crazy with it for about 20 minutes or so, then it will start backfiring on the left cylinder and start to run like crap. When I get back to the house it will only idle with full throttle, so I pulled off the left spark plug wire and the engine did not change at all but the plug is sparking. Just wondering if anyone else have had this same problem? Maybe when the engine gets that hot the valves are out of whack and will not create enough compression on that side, or might be a carb issue on that side.
Carb issue, pilot jet
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You need to check that you are getting power to both of the coils. It might not be a faulty coil.
The exhaust system has a balence pipe which is now open. You should have changed the exhaust (muffler) for the same type and fitting. Failure to do so can leave the engine running roughly. It is not as simple as just blocking off the balence hole. Things are there for a reason.
You should check that you have power to both coils before changing anything. With a fully charged battery you should see 12v plus.
One old bikes it is a good idea to renew the high tension leads and spark plugs anyway.
the balance pipe in the xs400 was to effectivley lengthen the pipe so they (yamaha) could fit a shorter silencer to get the look right and still comply with the regs.
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using electrolosis would be nice, but wouldnt it damage the paint? i assume i would have to submerge the entire tank to get it to work.
and what is a "lay up kit?" is it something to winterproof the engine? i was told to just drain all of the gas out of the carburetors, top off the tank, and add a stabilizer. what will the lay up kit do differently?
Just google "engine wise" and the top search is the kit!!
I thought that if you could seal the area around the pet cock after t has been removed and pour in the solution into the tank, you could achieve the same result.
I have used this method on brackets etc in a bath and it will remove the paint.
It also get hot depending on how much you insert the cathode (stainless rod) you do this at your own risk BTW don't come back to me with tales of woe
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Unfortunately, a Dutchman was killed at the tractor pull. He was crushed and died very quickly. Sad weekend.
I didn't know till this post!!
I had gone at 4:40 to beat the crowds so fortunatly didn't witness it.
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i have a yamaha tzr 50 which has been derestricted recently it has been cutting out after riding for about 5 mins then keeps doing it...i have had it apart and cleand out the carb fuel tank and such which went fine for about 3 days then same problem she cuts out i roll with her thwen she dies lights go out but the dash lights stay on i did notice that when i revved the oil light gets brighter depending on how much i rev....so i did it again and just 10 mins ago i went for a ride and if i try to for example kick it into 3rd gear she sounds horrible and wont go above 50KM she does do 90km max so yea then it feels like someone slammed on the breaks and i begin to slow down but i can stay at 50 if i keep in it 2nd gear
so any ideas about the first problem and maybe the first problem vcaused the second one...thanks in advance for ur advice
edit...i have also changed ghe spark plug i read about the ht lead but would that really cause these probems and she feels like she is wobbling a bit ont he road
the oil light should be off!! that means if you have no oil in your tank then the engine is partially seizing.
check your oil first
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I just got home from Tractor pullin' in Gt Eccleston Nr Blackpool
If you like engines, just look at this
8500 hp from 5 V8'salso jet engines a plenty
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Where can I find new(er) parts for a 1970 Enduro? I don't know the exact model code and so on but I do have a pic if that helps. Any information will help. Thanks.
code information from your engine or frame number here
try speed and sport
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thanks for the help guys.
i talked to my dad about this because we had the same problem with an old honda 3wheeler that we bought when i was about 12. we ended up buying a new tank, because they were so readily available, but he also suggested taking it to a radiator shop and having them steam/boil it out.
do you think that this is going to be a problem when i park the bike for the winter? if i top off the tank and put in some stabilizer, it shouldnt be a problem right? the tank should only have rusted where the gas was not touching, so if it sat half full for a while, the top half of the tank would be rusted. right?
you could always try this
and engine wise do a lay-up kit
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MY XS250 IS REFUSING TO START, FUEL IS GETTING THRU, POINTS HAVE BEEN GAPPED AND TIMING CHECKED, BUT I CANNOT GET THE SPARK TO JUMP THE GAP ON THE RIGHT HAND POINT, POWER IS GETTING THRU TO THE POINT BUT NO SPARK WHEN STARTER BUTTON PRESSED, I GET A SPARK ON THE LEFT HAND POINT. HELP
should not have any sparks jumping the points, your condensor has gone if it does!!
the points share a live feed which when closed "charge" up the coils.
to check your coils 4 ohms and 9.5k ohms should be measured on your coil wiring +/- 10% or swap over if one side is working.
I had problems with my bike bogging down under 5k revs and then trying to go over this. new plugs (iridium) cured this.
did you use the correct timing marks on the rotor? always use a strobe as when you tighten up the points the damn things shift, so i have to compensate so when it tightens up they are spot on.
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Take the tank off the bike and have it steamed out. This should remove any loose scale and rust. Do not put old fuel in petrol tanks as the fuel is hydroscopic. Make sure that the tank top seals are in good condition and not letting water in. Seal them with waterproof sealant.
Fit a fuel filter after the petcock.
Far as I know fuel is not hydroscopic (like brake fluid) water is present in the air (and in tank) and condeses. As water is heavier than fuel it sinks and guess where your fuel tap is?
that's why tanks are rustier at the bottom.
drewpy
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I have a 77 XS400 that I plan to rebuild/restore this coming spring. Currently, I am researching the parts list and one thing I can't find anywhere si the decals. I plan to repain all of the parts and such (gonna learn how to do this myself), and want to get the original decals to go under the clearcoat.
I have searched on many of the sites mentioned in other threads, but to no avail.
My fear is that I will have to take pictures and pay some oen to lay it out custom. My other thought is to get good images of it and have the decals custom made.
Any thoughts would be appreciated...
if you can post a pikkie of the decals I can maybe tell you where you may get them.
Its just that ther are about 4 different types for different countries and year!!
Post Script: found this on ebay but there is a 4th version,( I know as my friend has them on his)
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hey guys, im new to motorcycles, and am trying to teach myself about the engine, and engines in general.
heres the deal.
i own a 75 xs500b. it has been running fine, but yesterday i noticed a slight backfire when i rolled off the throttle.
today, it was even worse, to the point where the engine actually died when i got to work.
coming home from work, i was just wondering if i was going to make it. when i roll on the throttle the engine bogs down and tries to die (or just dies). when i pull in the clutch and roll off the throttle, all of a sudden the rpm's dont drop for quite a while (5 seconds or more) and then once it does die off, it just dies. doesnt want to start. backfires a lot.
im hoping that this is just a carburetor adjustment issue, that its maybe running way too rich.
any ideas or help would really be appreciated.
thanks.
jeff
check out spark plugs to see if they are rich, I doubt they are.
I have a feeling that you have some crud in your carbs especially the pilot jets as they give the rpm idle you describe.
The only fix is to strip and ultrasonic clean the carbs and fit new jets whilst your at it. get the keyster kits from ebay
gas tank sealer and petcock gaskets
in Classics
Posted
gasket from here
POR 15 is the stuff you want for sealing, check the prices and compare with the quote.