KR-1S.co.uk Forum

I'm losing it big time here. My KR1 seems to have a totally random state of tune. Sometimes it flies, sometimes the power goes flat and it refuses to rev out. Sometimes it packs up completely. So far, I have done:

Engine:-
New rings
New Small ends
New KIPS valves
New KIPS linkages
Cleaned tank out
Refurbed fuel tap
Cleaned carbs, set float heights and tried every needle setting
New carb inlet rubbers
Changed expansions from KR1 to KR1S

Electrickery:-
Checked all earths and added an extra one from cylinder head to regulator mounting plate.
Cleaned all electrical and fuse connections
New battery
Checked all electrical outputs as per manual (all normal)
Changed coil/HT leads
Changed regulator
Checked sidestand switch
Checked clutch cut-out switch
New plugs

...... and the effing thing still won't run right. The hotter it gets, the worse its moods become. It runs sweet on tick over and revs normally at a standstill. There are no fluid leaks and all fluid levels remain stable.

On the rare occassion it all comes right, she flies off like a scalded cat. However, most ride outs, it goes sick on me. It almost feels like the ignition is randomly retarding or a fueling issue. The longer you ride it, the worse it all gets. This KR1 is giving me serious OCD. Can anyone save me from ending up in the funny farm or setting fire to it?

Do a pressure test. Sounds like crank seals.

Cheers for the tip. If it was crank seals, surely it would be burning the gearbox oil or leaking into the alternator housing (depending which side the seals have gone). The problem is so inconsistant, I find it hard to believe the seals are randomly failing. Could it be sticking reed valves?

You mention it gets worse the hotter it gets. Just how high does the temp gauge get?
Also, how old are the plugs and which ones do you use? May be worth chucking in a fresh pair just to rule them out if they're not already new.

Plugs are new. Also tried Iridium. The bike runs at normal temp. I guess what I am saying is the longer you run it, the worse it gets. It doesn't actually overheat. Plug colour also looks normal, although I have not done a plug chop when it is running sick.

I'm wondering if it is some sort of electrical break down - hence changing the coil and rectifier. I guess I could carry on and do the alternator, pick ups, ECU, diode, wiring loom etc etc. This is the problem with random stuff. I wish whatever it is would just fail completely!

Check the petrol tank breather; If it's blocked, or restricted, you'll have fuel supply problems.

Hows your air filter ?

If it's not the fuel system (ie. random crud getting into carbs), then I'd be seriously looking at the stator. Many people have found that even though they may test fine according to the manuals specs, they can still be on their way out. Worth swapping out if youve got a spare one and a puller.

Thanks guys. I will check out the breather as this makes total sense, as the longer you ride it, the worse it gets.

Failing that, it is off to investigate the stator. However, I don't have a spare, so might end up on the scrounge to borrow one later. Anyone need a good coil and/or rectifier? I keep buying bits off fleaBay it doesn't need!

Man, am I going to give myself a good kicking if it turns out to be a blocked tank breather. Craig

I bet my money on the stator

I could probably use a spare coil and HT leads. Are they the same on the KR-1S?

Well I have been out for a spin and the same old routine took place. The fuel tank breather pipe is clear. When it started to go sick and gutless, I pulled over and opened the filler cap. No affect whatsover. Just so weird.

Just swapped the plugs to iridium and will give it another try, but the stator is looking like the prime suspect now.

As far as I am aware, the coil is same for both KR1 and KR1-S. I also have rectifier/regulator. By the way, once I get he flywheel off, is there anything I should be looking for re. failing stator etc?

I'll take a look in the electrical section of the forum for some tips. Is there a way to bypass all this cr@p and just run it on a total loss battery setup just to prove what it is by a process of elimination?

Electrics are not my strong point Craig. If you can't see it or hit it with a hammer, it's voodoo to me

How much do you want for the coil?

Whatever you are willing to pay. I paid £20 for it last week. I've tested it on the bike and it works fine. Say £20 including postage and packing?

That's fine, I'm just off to Aberdare for the weekend.

Drop me a PM with your PayPal details and I'll drop you a message when I get back.

Thanks, Ben

I'll bet Jan's money as well on either the stator /CDI