KR-1S.co.uk Forum

No time to play with it tonight
hard to say, but it's right now, probably 5-8mm static and 25-30mm with me on.
I set the airscrew at 1/2 turn. no idea why, i may have read it somewhere on here. Not sure why i'd do that when the factory setting is 1 1/4turns out either!
All the cables are set correctly, I reset the carbs using a 5mm drill in the slide, set the slide adjuster idle adjuster] and the drill is a very slight interference fit in both sides. Started it up and used an infrared thermometer on the headers to check the temperature. as you say, it's a sure fire way of know they're chiming in ok.
probably not going to have a lot of time to play the next few days. I'm pretty happy with it now. Just need to fit those new plugs!
Thansk for all the help and guidance!
Phil

philfingers wrote: I set the airscrew at 1/2 turn. no idea why, i may have read it somewhere on here. Not sure why i'd do that when the factory setting is 1 1/4turns out either!

might be me I

always advice to turn the airscrew less out than in the manual, about 1/2 turn would be my starting point. I found that otherwise idle is too lean and engine takes too long to reach idle rpm.

is that with the stock airbox and barrels etc and the stock pilot jet then Jan?
i must admit on my highly modded motor.1/2 to 1 turn out works ok but on the other that runs Gibson pipes and half lid off airbox and not as radically modded barrels 1 and 1/4 to 1/ and 1/2 works ok,wind it in any more and she loads up.
I reckon on the one im running at 1/2 out it would be better to go up on the pilot rather than have the airscrew so far in.
I guess there all a bit different to some extent as to what works best

like I said : it's always my starting point, not the final, but I doubt I ever turned them out to the original settings.

I have a standard box with filter, but with holes drilled in the upper lid on the sides.

people here often change pilot jets for richer ones. I've never done that and never felt the need.

and going up on the mains has no effect on idling.

Just re-read this thread as i was concerned about why Phils stock KR idle has increased to 3000rpm after adjusting the airscrew to stock.
Seems it was on 1 and 1/4 out to start,there's no reason another 1/4 of a turn should make a huge difference,i would definitely eliminate the idle speed adjusters then play around with the airscrew,if it needs 1 and 1/4 then set it to that.
Jan,i dont believe i said the main jet will effect the idle as such,what i did say/meant was if the main is too big when you get back on the throttle after shutting off that unburnt fuel is still there,regardless of throttle position,this could confuse things if you think "im only on a low throttle opening so it cant be the main,must be the needle/slide/pilot",so you end up setting a lean low/mid circuit to compensate for a too rich main.
This is a fairly new concept to me, ive never thought of it like that, but after having trouble with "part throttle" on my TZ V twin and messing about with needle jets and airscrews to no gain i sought the advice of someone who happened to be at the track who has far more experience than myself with the TZ's having run in European champs and a wildcard ride at the British GP,his advice was go smaller on the mains" even though to me it seemed ok at the topend" to cure the problem.
it worked.
what ive learnt is you never stop learning

I may have said they were 1 1/4 turns out but for some reason they were both definitely 1/2 turn out only, so a whole turn seemed to have made the difference. I'm hoping to get a run out on it today later. Will be checking the header temperature to be sure the balance is correct
I've been playing with an 851 this week, which I've imported from holland, so the KR has taken somewhat of a back seat.
The 851 has an 888 motor in I, which is believed to be an SP4/5 motor from the engine number, so I need to pull the rocker cover off to check the cams, which apparently is the surefire way to tell the spec. It's running single injectors tho, SPs ran dual. Tho not an issue if the fueling is correct

looks like I nailed the Kr1s too much last night and damaged it, lots of smoke coming out of the RH cyl, and sparks too, which i thought was the carbon clearing itself out after a blast! Fuel was overflowing from the carb that side too, odd as they were all cleaned and working well. I wonder if the float has split- are they prone to that? Exhaust [with laser temp gun- handy kit] was 100deg that side and 80 on the other side

float valves wear, it's a common thing. Have you inspected your pistons?

I usually clean the needle and seat and make sure the floats are correct a couple of times before changing needle valves. Probably a bit of dirt as it has been stood so long.

You might also check the floats aren't twisted.

I stripped the carbs and put them though the ultrasonic tank. They were spotless, checked the float heights they were perfect pretty much. No wear on the needle valves
No not pulled the top off yet.
When i get chance wil drop the exhausts off and have a little look.
Can you compression test a 2st?
do sure if all the smoke was petrol or water. havent checked the water level yet. I suppose should get the top of quickly if there is water in there
ar$e

floats dont usually play up too much but if they were sticking due to dirt or wear and flooding then this would cause an over rich mixture.
So what actually happened?
exhaust temp will play a part in where the engine peaks but if the water temp was stable,mixture wasnt lean it wont cause a problem as such.
did you ride the bike with the idle still revving madly or did you sort it out before testing?
Compression should be around 90 to 130 psi,they all vary a bit,anything below 90 is too low though.
Better bet to whip the pipes off and the plugs,if you can put a pic up of the plugs it may help to identify how she's running to some extent.
I hope the pistons are ok, as they did look quite worn in your previous pics.
you still running the pro 2 or have you swapped to the hein gerike stuff?
ATB

not done anything yet. Yes I sorted the idle out last week, hadn't checked it with the temp gun but it wasn't far away.
I was going about 110 in top, quuite close to the red line, can't be stock gearing, can't say i've checked.
yes still PRO2, RH exhuast looks oily as usual
Only reason they'd stick is dirt I'm sure, there was no wear evident really, i need to check the overflow to see which carbs is routed too but I suspect its the RHS. There were sparks coming out the exhuast with all the smoke, as it ticked over on the drive while I opened the garage door, I just thought it was carbon burning off.
Guess I need to pull my finger outn but this 851 I bought from Holland has just beccome road legal today and I'm itching to take it up the road.
It's got 'A' cams in it which suggest the motor is an SP2, 3 or 4. So should be good for about 110whp

here's a piccy

Erm,sparks out of the exhaust,reminds me of when i used loft insulation as silencer packing,was ok for a while then on the way back from chelsea bridge to hestons some guy pulled up along side shouting my engine had blown,apparently he was chasing (it as a high speed run ) for some time but backed off when the sparks started flying
Maybe it was just a load of old oiled up packing,that along with the carb flooding.
whip the plugs out,check the water and drop the pipes off,thats gonna take you all of 20mins,then you can play with the Duke (looks nice by the way)
only V twin i ever rode (4stroke) was a TL100R,was weird as i expected instant off idle grunt but no it was quite cammy with a big top end rush,shame it handled like a barge
ATB

you're right, grabbing a beer. . . . . . .into the garage, update in an hour!
only thing I'd not got around too was fitting those B9 EGV plugs that arrived last week

brings back memories of 88