Just picked up a KR, no spark...

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StotheH
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Just picked up a KR, no spark...

Post by StotheH »

Hi there fellow KR owners!

I picked up a KR on the weekend, knowing that it's not a runner. The previous owner told me that as best he could tell the CDI's were ok and so are the coils.
His story was that the alternator is shot. There's certainly no spark. All the lights work, indicators and the like.
I've downloaded the manual and had a go at trying the resistance tests using a multimeter but I got conflicting results on all the resistance tests I tried, Alternator, CDI's etc. So either all the electrical components are dodgy or my testing isn't up to scratch. Probably the later.

Now, I'm not any kind of auto electrician so all this is probably just a waste of time. I'll get it to a mechanic and have them check it out but it'll be good to know where to look.

So there's a bit of back story. On to the questions.

Are there any common electrical faults with these bikes?
Are there any good alternator windings floating around? In case it is that.
Do the resistance readings in the manual usually check out on an ordinary multi meter?

That's all I can think of at the moment, there are bound to be more questions.

Thanks in advance.

Sam in Tas, Australia.
StotheH
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Post by StotheH »

Would someone mind testing the resistance on their exciter coil so I can compare readings? It's the test detailed in 15-22 of the electrical section.
I get a reading of 2.5 or so on the white/red contacts as the manual
suggests but nothing on the black/red contacts. The manual suggests it
should be in the 90-170 ohm range.
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ScottaKR
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Post by ScottaKR »

I would, but mines off the road with electrical gremlins too. :(
KR250 Tandem Twin (Naked) :mrgreen:
KR1 Red/White
KR1S Track Bike (has been put on hold for now)
ZXR750 H1 (Winter project)
StotheH
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Post by StotheH »

Curses! I came home from the wreckers today all full of enthusiasm with 2 sets of CDI's in my bag. No dice, didn't make any difference. If nothing else that means my CDI's are probably ok.

My local wrecker has 6 or so sets of CDI's but not a single alternator winding. Plenty of side covers but they've all had the windings removed.

None the less, it was a good trip into the parts cave, I found a rear seat, a tank that hasn't rotted out a front fairing in much better condition than mine. None of that's going to do me any good though if I can't get the thing running :?

I called a wrecker about an hour and a half away who said he has a couple of good windings in his cave/shed/warren (you haven't seen a wrecking yard till you've seen this place) but he wants $150 AU for them. I'll have to wait and see if he's happy to have them back if it's not the problem.

Anyone feeling like braving the cold? Just gotta pop the seat and poke the ol' multi meter on there... It's really nice here in Aus at the moment if that helps.
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ScottaKR
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Post by ScottaKR »

:shock: $150 for a used stator? Pretty sure you could get one rebuilt for less than that.
KR250 Tandem Twin (Naked) :mrgreen:
KR1 Red/White
KR1S Track Bike (has been put on hold for now)
ZXR750 H1 (Winter project)
StotheH
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Post by StotheH »

Went back to my wreckers. I couldn't believe they had so many other parts but no alternator windings. Sure enough, hanging on the rack with all the other windings was a KR one. Even had a tag. Duh.

It looked pretty beat up but I put it in and bam! Big fat sparks.

No luck starting yet but my tank has holes all through it so getting fuel in is proving a messy job.
StotheH
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Post by StotheH »

Cleaned the carbs in an ultrasonic cleaner, gave them a scrub, filled the bowls up and boot. Started first kick.

Runs like a dog but it runs. I've got MASSIVE throttle delay. Once I manage to coax it up into the 5-6000rpm range it's snappy enough but down low... it'll stall before it revs.

Thoughts?
Luders
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Post by Luders »

It will be your jetting/carb setup.

Do you have the airbox connected?
StotheH
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Post by StotheH »

Yeah, everything is connected as standard. About the only thing I've checked so far is that the carbs are syncronised.
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smithyrc30
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Post by smithyrc30 »

ScottaKR wrote::shock: $150 for a used stator? Pretty sure you could get one rebuilt for less than that.
Small Coil Rewinds charge $200 for a complete rewind. They are in Geelong about 5 minutes away from where I attend work.

I had one done recently, made a big difference to the lights at idle :D
Luders
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Post by Luders »

Take the carbs off, give them a good clean and remove the pilot jet and make sure there's no crud blocking any of the holes. Also make a note of what size the jets are and let us know what your findings are.
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ScottaKR
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Post by ScottaKR »

Carb specs should be as follows.
Main jet 137.5
Option main jet 132.5, 135, 140, or 142.5
Main air jet (1.5)
Needle jet 0-6
Jet Needle 5DH2-4
Jet Needle Clip Position 4
Pilot Jet 35
Starter Jet 70
Service Fuel Level 4 +or- 1mm
Float Height 21 +or- 2mm

Copied from the workshop manual
KR250 Tandem Twin (Naked) :mrgreen:
KR1 Red/White
KR1S Track Bike (has been put on hold for now)
ZXR750 H1 (Winter project)
StotheH
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Post by StotheH »

Righto, I'll pull one out again and check the jets etc.
They're definately clean. I stripped them down, soaked them overnight, ultrasonic cleaned everything, then scrubbed them, then blew compressed air through everything.

To be honest I'm not convinced that both cylinders are firing at low revs. I'll take a vid and pop it on youtube, that way I'm not left trying to describe the symptoms.
98' VFR800Fi
75 KH400
84 KR250
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ScottaKR
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Post by ScottaKR »

StotheH wrote:Righto, I'll pull one out again and check the jets etc.
They're definately clean. I stripped them down, soaked them overnight, ultrasonic cleaned everything, then scrubbed them, then blew compressed air through everything.
Make sure your float heights are set correctly too, as it makes more of a difference than you may think.
StotheH wrote:To be honest I'm not convinced that both cylinders are firing at low revs. I'll take a vid and pop it on youtube, that way I'm not left trying to describe the symptoms.
If your not sure if one is not firing at low revs, check how warm the expansion chambers are getting. If one is markedly warmer than the other, then the cold one is your problem cylender.
Have you checked both spark plugs for a nice strong blue spark?
Have new plugs been fitted?
KR250 Tandem Twin (Naked) :mrgreen:
KR1 Red/White
KR1S Track Bike (has been put on hold for now)
ZXR750 H1 (Winter project)
StotheH
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Posts: 21
Joined: Mon Dec 12, 2011 11:21 am

Post by StotheH »

I fitted a new (old) tank today so I could run the bike for more than 15 seconds at a time. Once it had been running for a minute or so it all settled down. Still not very snappy throttle response down low but definately running better. It is firing on both cylinders.

Initially I was only getting exhaust smoke out of the rear cylinder. I was running the oil pump and premix so I found that a bit odd. Again, once it warmed up it was chuffing away from both.

I'll let it warm up properly once I've got the coolant flushed out and topped back up again. I think it's well overdue for a de-scale, the green coolant that went in the other day is already brown.
98' VFR800Fi
75 KH400
84 KR250
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