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1Back to top Go down   Difficult to Start when Cold Empty Difficult to Start when Cold on Thu Dec 11, 2014 5:49 pm

Tom FKR

Tom FKR
Life time member
Life time member
G'day All, the additional 86 K100RS in the shed is just about ready for rego. Changed HT leads and coils and now runs on all 4!!!!!. BUT it is difficult to start when cold. I suspect it is the temperature sensor stub, the heat sensor relay or the ECU. Can anyone of you learned members please enlighten me. Thanks in advance. Cheers Tom

    

2Back to top Go down   Difficult to Start when Cold Empty Re: Difficult to Start when Cold on Thu Dec 11, 2014 6:08 pm

Inge K.

Inge K.
VIP
VIP
The relay have nothing to do with this, it only starts the fan and warning lamp.

I would suspect the temp. sensor (or its connections), easy enough to check.

Measure the resistance between contact #10 and 13 at the injection ECU connector
(female side).
Count from the rear end, also the empty slots.
In the troubleshooting guide at the portal you find a table, resistance vs. temperature.


__________________________________________________
Inge K.
K100RS -86. (first owner), K1100LTSE -94.
    

3Back to top Go down   Difficult to Start when Cold Empty Difficult to Start when cold on Thu Dec 11, 2014 6:19 pm

Tom FKR

Tom FKR
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Thank you Inge, will do that and let you know the results. Cheers Tom

    

4Back to top Go down   Difficult to Start when Cold Empty Re: Difficult to Start when Cold on Thu Dec 11, 2014 7:23 pm

RicK G

RicK G
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One thing I have found Tom is that some of the K100s don't like even a slight touch of open throttle at start up.
My grey K100 and a few others I have come across were like it to the extent that you remove your hand from the grip when starting cold, just push the button with your index finger and don't touch the grip and when it fires let it do what it wants to do, it may stop in which case hit it again, mostly it just idled and then after about 10 seconds it would accept a touch of throttle and all was good to go. But even the slightest touch of throttle made it very cantankerous and difficult to get going. I spent 2 years trying to make it easier to start but just gave up and accepted that it was to be.
Bosch do say don't touch the throttle but it usually doesn't make them cranky.
I have had 2 Ford cars with similar EFI and both would let you know if the throttle was pushed before starting by being a bit harder to start.


__________________________________________________
"Man sacrifices his health in order to make money.
Then he sacrifices money to recuperate his health.
And then he is so anxious about the future that he does not enjoy the present; the result being that he does not live in the present or the future; he lives as if he is never going to die, and then dies having never really lived."   Dalai Lama


Bikes 1993 K1100 LT, 1998 K1100 LT, 1993 K75 RT, 1996 K75RT, 1986 K75 GS, 1979 Z1300 Kawasaki X 2 for now
    

5Back to top Go down   Difficult to Start when Cold Empty Difficult to start when cold on Thu Dec 11, 2014 7:39 pm

Tom FKR

Tom FKR
Life time member
Life time member
Thanks Rick, I have found it to be similar to your description. It will take about 4 hits on the starter without touching the throttle. After starting it splutters a bit but then settles into a good idle. Maybe it's a case of a grumpy old K in which case the K and I are very compatible. Cheers Tom

    

6Back to top Go down   Difficult to Start when Cold Empty Re: Difficult to Start when Cold on Thu Dec 11, 2014 8:13 pm

RicK G

RicK G
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That was about what I had figured with mine, it was just grumpy like its owner.


__________________________________________________
"Man sacrifices his health in order to make money.
Then he sacrifices money to recuperate his health.
And then he is so anxious about the future that he does not enjoy the present; the result being that he does not live in the present or the future; he lives as if he is never going to die, and then dies having never really lived."   Dalai Lama


Bikes 1993 K1100 LT, 1998 K1100 LT, 1993 K75 RT, 1996 K75RT, 1986 K75 GS, 1979 Z1300 Kawasaki X 2 for now
    

7Back to top Go down   Difficult to Start when Cold Empty Re: Difficult to Start when Cold on Thu Dec 11, 2014 8:45 pm

JR_K100RS

JR_K100RS
Life time member
Life time member
G'day Tom , my K is also a reluctant starter in cold weather , I spoke to my mechs about it and the first thing they asked me is what octane fuel I use ( 98 ) , he suggested I try a tank of 91 to see if it made a difference , sure enough instant start in similar temps ( cold winter 1st thing in the morning ) , he explained the higher ratio's of octane improver's etc , this is just my experience in a similar situation , don't flame me !

John R


__________________________________________________
Diamond Grey ( 617 ) 1987 K100RS ( European Delivery ) Original owner
    

8Back to top Go down   Difficult to Start when Cold Empty Difficult to start when cold on Thu Dec 11, 2014 10:18 pm

Tom FKR

Tom FKR
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Life time member
Thanks for that info John. Will try the lower octane fuel and see what happens. Will let you know. Cheers Tom

    

9Back to top Go down   Difficult to Start when Cold Empty Re: Difficult to Start when Cold on Fri Dec 12, 2014 1:42 am

Holister

Holister
Life time member
Life time member
Hi Tom. Lean fuel mixture can give these symptoms. That could be caused by different things. Temp sensor as Inge sugested. Also look at the fuel system. Low fuel pressure caused by dickie pump or regulator, blocked filter or patially blocked or faulty injectors. If it's spluttering a little when she fires up sounds to me like its a little starved. How does it respond when you give it a fistfull? Does she hesitate? Also, how do your spark plugs look?

Cheers


__________________________________________________

1989 K100RT     VIN No.  0097367 (naked)  
1996 K1100RS   VIN No.  0451808
 Difficult to Start when Cold Austra12    Fuel:  95 Octane
Engine Oil: Nulon Full Synthetic 15W50
Gear Box Oil:  Nulon Synthetic 75W90
    

10Back to top Go down   Difficult to Start when Cold Empty Difficult to start when cold. on Fri Dec 12, 2014 2:38 am

Tom FKR

Tom FKR
Life time member
Life time member
G'day Nige,thanks for the input. Plugs are new but will take them out to check condition.Fuel filter is new and it will not rev up until well warmed up. It dies when trying to rev when cold - ie after start up.Will check the injectors next as well as heat sensor unit as suggested by Inge. Will report back soon. Cheers Tom

    

11Back to top Go down   Difficult to Start when Cold Empty Re: Difficult to Start when Cold on Fri Dec 12, 2014 4:14 am

Holister

Holister
Life time member
Life time member
Re plugs... just looking for signs of lean/rich fuel. Will give you a bit of an idea about what's happening.
But from what you've described, my money is on exhuast valves. Could be a good idea to check the clearances to see what's happening there even if to just rule that out. I have the valve tools and a few spare shims. Will drop them in when I'm in Newcastle in a couple of weeks.
Cheers


__________________________________________________

1989 K100RT     VIN No.  0097367 (naked)  
1996 K1100RS   VIN No.  0451808
 Difficult to Start when Cold Austra12    Fuel:  95 Octane
Engine Oil: Nulon Full Synthetic 15W50
Gear Box Oil:  Nulon Synthetic 75W90
    

12Back to top Go down   Difficult to Start when Cold Empty Re: Difficult to Start when Cold on Fri Dec 12, 2014 4:20 am

RicK G

RicK G
VIP
VIP
When you first posted I didn't realize it wouldn,t rev till warm. I agree with Inge and that it is fairly symptomatic of the temp sensor going low resistance or short circuit. The poor old computer thinks it is already hot and wont supply fuel at the correct ratio till it warms up. If you do need a sensor give me a yell I probably have 5-6 round here.


__________________________________________________
"Man sacrifices his health in order to make money.
Then he sacrifices money to recuperate his health.
And then he is so anxious about the future that he does not enjoy the present; the result being that he does not live in the present or the future; he lives as if he is never going to die, and then dies having never really lived."   Dalai Lama


Bikes 1993 K1100 LT, 1998 K1100 LT, 1993 K75 RT, 1996 K75RT, 1986 K75 GS, 1979 Z1300 Kawasaki X 2 for now
    

13Back to top Go down   Difficult to Start when Cold Empty Re: Difficult to Start when Cold on Fri Dec 12, 2014 4:59 am

charlie99

charlie99
VIP
VIP
easy to test that bit ,,,but hard to get at with right hand side lower fairing on tom

do as inge suggests first up

good luck mate.... hope that's it .


__________________________________________________
cheezy grin whilst riding, kinda bloke ....oh the joy !!!! ...... ( brick aviator )

'86 K100 RT..#0090401 ..."Gerty" ( Gertrude Von Clickandshift ) --------O%ODifficult to Start when Cold Au-log10

"redframe" rs "bitsa"  with many contributions from the k100 community ,,with many thanks
    

14Back to top Go down   Difficult to Start when Cold Empty Re: Difficult to Start when Cold on Fri Dec 12, 2014 6:07 am

92KK 84WW Olaf

92KK 84WW Olaf
Life time member
Life time member
I have to use the 'choke' when cold and in winter. If I don't starting is not good, but when I use it I can get
a nice steady tickover. Once warmed a little all is well.

Plugs are NGK D8EA and always come out the right colour. Lots of debate about using NGK 7DEA but my buddy who is ex BMW always goes for no 8 and he knows the Ks well. [To quote: 'The only time I ever had to work inside a K engine was to repair crash damage, never had a failed engine']. He regarded use of the 'choke' as normal.

I haven't noticed a problem with pick up and after about a mile I can back off the 'choke'.


__________________________________________________
1992 K100LT 0193214 Bertha Alaska Blue 101,000 miles
1984 K100RT 0022575 Brutus Baja Red bought 36,000 now 89,150 miles
1997 K1100LT 0188024 Wotan Mystic Red 58,645 now 98,780 miles
1983 K100RS 0011171 Fricka 29,495 miles Damn K Pox Its a Bat outta Hell No 32,600 miles
    

15Back to top Go down   Difficult to Start when Cold Empty Re: Difficult to Start when Cold on Fri Dec 12, 2014 9:36 am

Comberjohn

Comberjohn
Life time member
Life time member
Not going to get technical with sensors and stuff but does the 'choke' lever increase the throttle opening slightly when used?
In other words, if you hold the choke lever on, does it keep the revs up a bit higher than tick over?
Easy adjustment if it doesn't.
They can be odd, too.
My '89 needed a short press of the starter and then another press before it would start. The '84 just gave a cough and started instantly. Even if it had been sitting in sub zero temperatures for a week!


__________________________________________________
Life is not a rehearsal.
2010 VFR 1200F DCT 
2010 R1200GS(gone)
1986 K100 Silver(gone)
2012 K1600GT(gone)
1984 K100RT Madison Silver(gone)
1989 K100LT Stratus Grey(gone)
1984 K100 Red(gone)
http://www.johnsdrivingschool.co
    

16Back to top Go down   Difficult to Start when Cold Empty Re: Difficult to Start when Cold on Fri Dec 12, 2014 10:13 am

92KK 84WW Olaf

92KK 84WW Olaf
Life time member
Life time member
Spot on Comberjohn, hence my 'choke' rather than merely choke. It simply applies a small amount of throttle opening and does not alter fuel/air ratios etc. My K has been sitting now for 6 weeks so a good time to try it.


__________________________________________________
1992 K100LT 0193214 Bertha Alaska Blue 101,000 miles
1984 K100RT 0022575 Brutus Baja Red bought 36,000 now 89,150 miles
1997 K1100LT 0188024 Wotan Mystic Red 58,645 now 98,780 miles
1983 K100RS 0011171 Fricka 29,495 miles Damn K Pox Its a Bat outta Hell No 32,600 miles
    

17Back to top Go down   Difficult to Start when Cold Empty One should check on Fri Dec 12, 2014 4:28 pm

ibjman

ibjman
Life time member
Life time member
One should also check for lower than spec compression. Low compression can cause this also.

Regards, Ibjman

    

18Back to top Go down   Difficult to Start when Cold Empty Difficult to start when cold. on Fri Dec 12, 2014 11:55 pm

Tom FKR

Tom FKR
Life time member
Life time member
G'day All, thank you for all the input. Got the wrong readings on pins 10 and 13 on the ECU. Changed over the heat unit sensor behind the radiator and got the right readings for pins 10 and 13. It now starts to fire first up but  still won't idle or rev happily until warm. Next step is to put 91 oct.fuel in it and check compression. Cheers Tom.

    

19Back to top Go down   Difficult to Start when Cold Empty expect on Sat Dec 13, 2014 12:59 am

ibjman

ibjman
Life time member
Life time member
Expect it to require the "Choke" on the first step until you've driven at least a block or two. As discussed before the Choke is actually nothing more than a fast idle device....does not set mixture.
 You might run a bottle of chevron techron fuel injector cleaner through it.

Also.......I don't recall if you've tested the fuel pressure yet. 
Regards, Ibjman

    

20Back to top Go down   Difficult to Start when Cold Empty Difficult to start when cold on Sat Dec 13, 2014 2:26 am

Tom FKR

Tom FKR
Life time member
Life time member
Thanks Ibjman,  a fuel pressure test has not yet been done but is on the list. Have given up for the day - need a cold beer. Cheers Tom

    

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