As others say, looking like a bad plug. Yes, it really can be as simple as that, I hope this time the mystery problem packs it bags. Truly I do!Swapped plugs over and RIGHT SIDE IS COLD!..............Aaaargh.... can it be as simple as that?
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What have you done to your XS today?
- Thread starter I am Carbon
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- maintenance
Champion plugs? ..... well, I would never ...... An old friend of mine worked at the local Honda shop back in the '70s. He said Champions came in the new Hondas back then and they wouldn't even use them. They'd pull them out, bag them up, and give them back to the distributor, installing NGKs instead.
Exactly when it happened, they must have had some serious QC problems.
Raymond, we will see tomorrow; picking up 6 new non resistance plugs in the morning. If this is what stopped me running my dream bike the whole summer…..
I might just get pi$$ed…….. I might anyway.
Im still sceptical however.
Yeah... best hold yer beer Ads... pretty sure you have a bad plug. Not so sure what else might be lurking. One step at a time mate....
11k miles today on this 78E virgin unopened XS650 (46 year old) engine. Original clutch. Even the points are still the original tho due for replacement.
Running as strong as ever and not even dripping a drop of oil , not even the clutch rod seal.
Yes, the rest of the bike has been through a beating and upgraded but that 78 era engine is tried and true stock !
Yamaha Quality from the 1970’s ! Actuality amazing !
Attachments
An air gap increases the voltage tending to made a fouled plug work again. They used to sell them in the back of magazines. A suspicion would be oil getting in that cylinder.
I do believe the points are at the end of life.
These mufflers are cool but the carburetion prob needs improved tuning yet to be found? I am interested in the 5Z1 slide needles along with one more size up on mains, new points next spring..
These mufflers are cool but the carburetion prob needs improved tuning yet to be found? I am interested in the 5Z1 slide needles along with one more size up on mains, new points next spring..
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Love the colour scheme of green and gold. Handsome bike!
I don't know why y'all got onto the nitrogen wagon... but I guess I started it with my interest in the variable permeability of inner tube materials, specifically buna vs latex... but there must be many "rubber" mixtures and molecular ways of being...
The fix, maybe, is to use a gas with a fatter molecule. R134a is the trial candidate. This is what ah done ta ma XS to-day...
My XS (the runner anyway), has "slowleak" front tube. The sporty, also tube, does not... I suspect the trouble is the tube material in one is more permeable than the material in the other.. The XS has a sexy front brake setup with dualdisk and the lazy ol'feller is not inclined to pull the thing down until he's pretty sure...
Nitrogen and air are obviously unsuitable in the instance, since they "leak" out over several weeks in the subject machine.
'bout time to change the oil and clean off some crud... Still fine riding weather, though a jacket is nice.
Maybe take the old gal to the bar... sadly the one in the video is closed now
But there's another, a new one, a bit closer... (I don't know the fellas in the video, just the road)
Best! 40N
The fix, maybe, is to use a gas with a fatter molecule. R134a is the trial candidate. This is what ah done ta ma XS to-day...
My XS (the runner anyway), has "slowleak" front tube. The sporty, also tube, does not... I suspect the trouble is the tube material in one is more permeable than the material in the other.. The XS has a sexy front brake setup with dualdisk and the lazy ol'feller is not inclined to pull the thing down until he's pretty sure...
Nitrogen and air are obviously unsuitable in the instance, since they "leak" out over several weeks in the subject machine.
'bout time to change the oil and clean off some crud... Still fine riding weather, though a jacket is nice.
Maybe take the old gal to the bar... sadly the one in the video is closed now
Best! 40N
Mike Melvin
XS650 New Member
HAVE A COUPLE OF OLDER XS 650'S COLLECTING ALL PARTS TO POSIBLE SELL.
Put this in the For Sale section, and you'll attract more attention to your stuff.
Made some progress today. New plugs and dressed copper leads.CHASING THE PERSISTENT MIS-FIRE ON TAFFY
A day off today, Mrs C is out with a friend, so down the shop and a chance to investigate the mis-fire.
Seat and tank off. Remote fuel supply on. Iggy on and press start.
As usual Taffy fires up straight away but only on the right. Left is cold.
Swap leads over but left is still cold...
Take out left plug and crank over...Spark is very intermittent.
Replace both spark plug cables from hi-tech carbon core ones to nice new copper ones.... Still no joy.
Pull left plug out again and crank.. Intermittent weak spark... but strangely gets a strong spark as I pull plug away from block.
Reinsert plug to cylinder, fire up and left still dead; gently pull cap off plug whilst bike is running and it bloody fires. Push it on and nothing.. pull it off and fires.
Fires when cap is hovering over threaded connector, but not directly connected.
What evil witchcraft can this be?
Bikes fired up cleanly and ran well. Warmed up to temp choke off and steady idle. Ran for 10 minutes at a number of differing revs, all good.
Too wet for a test ride, which will be the acid test of success.
More on my build thread.
Fingers crossed
!
Yesterday I realized the rear brake pads were only contacting the disc rotor with the top half of the brake pads, I had the same issue last year and replaced the disc rotor and caliper hanger and the brake seemed to work well.
I removed the caliper and by pumping the brake pedal could see the piston push out then retract when I let the pedal return to it's stop.
I used air pressure to pump out the piston and blew out the entire system and half filled the piston bore with clean brake fluid, installed the piston and tried to push the piston back in using a f clamp. The only way to get the piston to push in was by opening the bleeder which doesn't seem right I thought it would push the fluid back into the master cylinder reservoir?.
I have tried bleeding the whole system but after the first squirt I'm not getting any fluid.
I filled the caliper through the banjo bolt hole and the bleeder hole after installing the piston and even tried a hose on the bleeder to a large plastic syringe and cracked the bleeder and try and suck the fluid through but get nothing.
Can't see any leaks and fitted new copper washers and thread tape on the threads.
Guess I should have left it alone,at least they worked?
I removed the caliper and by pumping the brake pedal could see the piston push out then retract when I let the pedal return to it's stop.
I used air pressure to pump out the piston and blew out the entire system and half filled the piston bore with clean brake fluid, installed the piston and tried to push the piston back in using a f clamp. The only way to get the piston to push in was by opening the bleeder which doesn't seem right I thought it would push the fluid back into the master cylinder reservoir?.
I have tried bleeding the whole system but after the first squirt I'm not getting any fluid.
I filled the caliper through the banjo bolt hole and the bleeder hole after installing the piston and even tried a hose on the bleeder to a large plastic syringe and cracked the bleeder and try and suck the fluid through but get nothing.
Can't see any leaks and fitted new copper washers and thread tape on the threads.
Guess I should have left it alone,at least they worked?
just my hunch, but the tiny compensator hole in master cylinder may not be open, ie pistorn retraction in mc is obstructed...just maguez.
A vacuum bleeder that hooks up to your compressor is a charm of a tool to have when bleeding breaks. They will suck fluid so fast you however have to make sure your on top of things at the MC resevoir so air does not get to the holes in the MC.
On Taffy:
Cleaned up some ground connections and re-soldered with copper connectors. Taped a small hole in the frame under the tank to take the hex bolt that secures the grounds to the frame; cleaned off frame paint to ensure good grounds.
On The Brat:
Bought a power take off plug in for the loom. Located the female socket on the loom which was taped over just behind the head-stock.
Soldered (hard wired) the leads on the Quad-Lock charging head to the power take off pig tails. Located the Quad-Lock assembly just behind the bikes screen. I now have constant ignition switched charging for my I phone / satnav. No more dying batteries as I ride.
Cleaned up some ground connections and re-soldered with copper connectors. Taped a small hole in the frame under the tank to take the hex bolt that secures the grounds to the frame; cleaned off frame paint to ensure good grounds.
On The Brat:
Bought a power take off plug in for the loom. Located the female socket on the loom which was taped over just behind the head-stock.
Soldered (hard wired) the leads on the Quad-Lock charging head to the power take off pig tails. Located the Quad-Lock assembly just behind the bikes screen. I now have constant ignition switched charging for my I phone / satnav. No more dying batteries as I ride.
