Dear K team!

i guess the problem is temperature related as it all started when the weather started getting more and more chilly. at the beginning, when the temperature dropped to around 15 degrees celcius. When starting the engine it bugged and knocked like crazy for the first 2 minutes but it was starting from the first spin.

today, after 4 days of not riding it, the temperature dropped to 6 degrees and for the first time since june i couldn't start it at all - the engine sounded like flooding and there was a lot of fumes coming out from the exhaust. after a couple of attempts i opened the throttle a bit and somehow it started. after a minute or two the situation was bearable and after 2 more mins everything seemed ok. can it be the temperature sensor behind the radiator? my engine started getting a bit rich in the past few weeks (my exhaust got black) but it was not a problem until today.

any suggestions?

It could be oil viscosity being too heavy for the cold weather ??

nah, i have 10w40 in my engine...

good point toto ...paj ...what viscosity oil do you have in ? time to go back to a 10-30 ? maybe even time for a filter change when you do ?



as i dont know what the folks up your way use i can only guess ....maybe some of the canuks can elaborate ? although they still maybe not as high up as you ...

as i said, the oil is 10w40 so it's fine. i have 15w40 in my car and it starts like a baby even in -20. like i said, the engine was definately too rich at the startup and in my opinion the problem is somewhere around that.

i think i have seen a graph of the temp to water temp sensor here somewheres ....but i dont think ive seen a graph of the air intake sensor ... although we have seen an air intake sensor clean up solve a couple of issues ...be carefull they are a sensative piece of stuff and using the wrong solvent will kill it completly

so you mean that the temp sensor in the AFM can be the issue? in my opinion, with the throttle closed it's not that influent, is it? i know about the chart you're talking about - i have it but it seems that it need super exact measurements (especially when it comes to temperature).

hmm maybe a simple test would to be to get some heated water and pour it over the air filter box ...leave it for a couple of minutes and try again ..( from cold of corse ) ??? worth a try ...eh ?

but why does it get better so quick then? just after 2 mins

i had a similar problem with my k100..initially it was the rough idle and eventually the bike refused to start. it backfired, black smoke poured out of the exhaust and the loud knocking sound....

i tried all sorts of solutions...cleaned the AMF, the electrical connections, replaced the spark plugs, checked the ECU, the ignition unit and every other electrical component with a multimeter....no luck...........

eventually i replaced the battery and it was running like a swiss watch...unbelievable to think that a simple but important component was the cause of so many problems.....

my advice to you is to look at the simple solutions and dont over complicate the situation.....when you think about it...cold weather puts the most demand on a battery and when you consider a k100 has electronic fuel injection it's important that you have a battery that can hold it's charge....

my battery was failing but i didnt realise that recharging a battery is not sufficient..the battery MUST BE ABLE TO HOLD ITS CHARGE..measuring 12 volts across the terminals is no guarantee the battery is going to do its job....

whatever you do and before you throw good money replacing parts in the false hope its going to solve your problem is not the way to approach this problem....i dont think its got anything to do with the oil...

anyway...good luck

good point Gabriel! even though the previous owner told me that the battery is brand new (it looks like it as well) it won't hurt to check that first! thanks, i'll let you guys know. maybe i'll take it out today and charge it overnight - i have a charger which can refresh even the oldest batteries;)

great point gabriel ...many dont "do the basics" first

pajonk wrote:i have a charger which can refresh even the oldest batteries;)

Magic!? I`ve got plenty of them in my shed, sending down a truck during the week.

Inge K.

check the ignition leads and coils paj .......mine was unpredictable idle at cold ....after i changed the number #1 lead and almost all my ignition problems dissapeared .

Good point Charlie.
If I don`t remember wrong Pajonk also had an issue with spark eroded plug caps and missing adaptors some time back.

Inge K.

Inge - the charger i have was made by my father (he's an electronics engineer) and he claims that it can desulphurise (can you say that in english??) any battery hahaha - i don't know if i should believe him but it used to do magic with my motorcycle batteries.

charlie - i changed all the HT leads and caps a while back so this should be fine i guess. as i said, the bike has problems with starting but as soon as it starts things get better in a matter of seconds - maybe after it gets some charging power from the alternator and the battery is just really dead?

i have to check that tonight.

good work paj ...i just feel that i have to point out the simple steps to do first .......measuring them again cost nothing ...but it could show up something in the measuring and is just a step in the process of doing that ...i remember going for a ride over the mountains with twb ....along the way i felt a strange vibration ...like it was missing at certain speeds ...any how i had checked it all ....a few hours before ,,,i undid the plug cover and high tension cover over the coils ..and reseated them all ...problem solved ....another 2,500ks later i havent missed a beat and the vibrations disapeared totally .....(there are other issues but not with the spark ) old bearings and rubber seals i expect ))

I would say that if the battery has the grunt to start it then it should be OK with the ECU and CDI but they don't call it electrickery for nothing.

Please don't forget that the temperature sensor in the AMM determines the fueling during starting up, the engine cooling water sensor takes over when the engine starts to run. Do you use the choke??
It might be that the engine adjustment needs to be checked

hey guys,

i had a company party last night so wasn't able to look at the battery at all. i want to take it out tonight and here's a question - is it complicated? it looks like the battery is in the least accessible part of the bike. is there an easy way? after that test i will try to look at the AFM sensor.

the bike started pretty easily this morning even though the temp was the same. as i said earlier, when i was starting the bike yesterday (when i had the problems) the bike wasn't ridden for a couple of days so who knows - maybe the battery was weak. to be honest, since i got the bike in june i rode it technically every day;) that was, i guess, the longest break i had. anyways, i'll keep you updated!

cheers y'all

it seems that the problem may have been solved (the battery is still charging but i am not sure if even my father's magic charger will do the trick). when i was buying the bike (june) the owner told me that the battery is new (he must've washed it super properly as it really looked like brand new when on the bike!). i took it out yesterday and wham! it's old as sh*t, 3 cells where half dry and it's general state is, i would say E-... i guess it's time for a new battery but because of the fact that i live in poland and it's almost november, i'll try and use the charged one and get a new one in spring.

thanks for all your help guys, and THANKS Gabriel!