cant get the kh250 started

banjodeano · cant get the kh250 started

i am having trouble getting the bike started? where do i start, i had the frame painted, put back on all the wiring, put back the rebuilt engine and carbs, i get a spark at the plugs (sometimes) but it wont fire up, (well on one cylinder and then cuts out) it has a new battery that goes flat straight away...i know it could be a million things, but where do i start, i am a complete novice, it has an electronic ignition fitted and no points..thanks guys..

The Wolfman

You're right its a broad description and difficult starting point, but...
for the electrics, just make sure all the wires go where they should and that the connectors are clean.
Don't forget the wires start at the pickups and end at the plugs, most things between can be swapped around to try and move the fault around too.

If you have any carb suspicions, swap a couple around see if the fault moves too.

banjodeano

Thanks Wolfman...i think the carbs are ok, i have taken them off and cleaned them well, i am sure they are working ok, i think i must have the wiring wrong, the battery can go from fully charged to flat in ten mintues

The Wolfman

That sounds like the battery should be bubbling and getting warm, and also something else should be getting warm too, have good feel and smell around.

At this point it would be a good ploy to disconnect the battery and put a small (say 4a) battery charger on the terminals as constantly charging the battery is just wasting your time and effort.

You can see what current is being drawn with the ammeter of the charger, it should be negligable with just a neutral lamp.

Right so.... do you have much current with ignition turned on or whether it's on or off?

Errhmmm, this is gonna get complicated, might be better to ring me from the garage, you have a PM.

But before you ring it might be quicker to have the seat up/off, side panels off, headlamp open and possibly the tank off too

180kid

nice one Graham...

thats the beauty of these bikes, many people are scared to death of em,
ooer 3 cyls, stick with it and it' wont be long before ya' can build em' and trouble shoot what a lot cant do,..quite simple when you done afew, much more satisfaction to do it yerself,...dont get too ragged will be something simple,

banjodeano

Thanks wolfman, i got your number...will send mine..
the bike is not complete, it is basically just the engine in the frame, i didnt want to reassemble it all to find i then have to take the engine out again, the bike had been stood 10 years and was seized, i thought the best thing was to try the engine after new pistons and rings, so i mounted the wiring looms as correctly as possible, fitted engine without exhausts etc just to try, it has the downpipes fitted from the engine though, and though i would see what it sounded like...
i have a battery charger, a normal 12v one, is that ok? two days ago it spluttered on two cylinders, now it wont even splutter on one..i have swapped plugs about, and also took the carbs of to re clean...
year your right 180kid...i am bricking myself...this is like brain surgery to me, but i feel even tho i have only had it a couple of weeks i picked a lot up..
thanks guys...

banjodeano

180kid

black n decker, old school,..

try your timing, although that wont be the battery drain prob, sounds like thats shot too now, boiled, get a spare un'

just loosen the back plate screws and move boyer about, marks approx 25 too the hour, earths can be a prob on powdercoated frames, with paint you should be ok but its sacriliage to even scratch a new painted frame hey its what ya have to do to get the earths working around coils,

will get the degree for timing for boyer, although like said just move the plate around when running,...all bikes i've done this way its all set the same. you cant time it (timing light) proper if its not running with boyer,

mish mash for future ref,..

banjodeano

Thanks 180, i had tried moving the plate about, but it didnt make any difference..one other thing about the battery draining quick, i noticed that when the engine cut off switch was tuned to "off". the neural light went very very dim...

bubba2

Get a in line coil tester cheap as chips then you can kick the bike over and see if you get a good spark .nearly bought coils for mine its just s lot of hassle trying to kick it over and see if you got a good spark . my frame was powder coated a little scrape no probs BUT THE CARBS WILL PLAY YOU UP BIG TIME .had mine running on three on carb cleaner !! put petrol through nothing but hassle and get the wright plugs hcs good luck

180kid

banjodeano

Thanks for the tip Bubba, all advise is greatly appreciated... i have been talking to Wolfman about the problem, it seems to be loosing charge very quickly.. withinn minutes even, Wolfman has a better understanding of the problem than me, we are not sure but it may be an electronic ignition fault, its all rocket science to me tho

The Wolfman

The short on the 12v is definitely caused by the boyer, we have disconnected and eliminated everything else, the question is why?

When we disconnect the 12v feed (yellow) into the boyer, the short on the 12v supply disappears, reconnect it and the voltage is killed again.

If we disconnect each of the coils in turn, then voltage returns per disconnection until the last coil then 12v is fully restored.
when we reconnect the coils again in turn the voltage falls accordingly with each reconnection, the order of discon/reconnection does not matter.

No problemo, definitely the Boyer.

But... Deano has since sourced and fitted a new Boyer. NOW I'm struggling, have we got two units with the same mysterious fault?

Email sent to Boyer Technical and I'm waiting a reply.

banjodeano

Nice work Wolfman....

ThreePipesSmokin

bubba2

A mate of mine says with boyer s on a british bikes !! you should get a spark when you turn the ingnition on !! not sure about jap stuff but he says send it back to the factory for testing and they'll probley send you a new one free of charge ! put a dyna on a z1r i had. fryed a coil then holed a £100 cosworth piston went back to points ..

The Wolfman

Yes they should all spark when the iggy is switched on, in practice it doesn't always happen, and it's not a problem just a design oditty that the marketing dept choose to call a feature.

Having said that, on a points setup you can sometimes get a spark on one plug when you switch the ignition off.

The Wolfman

Right Deano, we had a response from Boyer, not quite what I expected...

They reckon that when running 4a could be about right!!??**##? fk me that's a lot.

But when standing there should be negligable current drawn.

I think a trip to yours is gonna be on the cards, but before I do, I'll make some checks on my own bike.

simonh

jesus no wonder you need a good battery

how about running a dual battery option, one in the tail as well

kas750

told ya boyers r wank!!!

180kid

told ya boyers good, never had a problem with it, that wernt the battery's fault,...

kas750

you just need a top box with a tractor battery in it

180kid

yup, sure can kill em' if charging system dont work its flat every few wks, on a good charging bike seems ok, although the Gel type battery is a big improvement for longevity, fits in the tail, just nice, lasted 3yrs my last one, even laid up over the winters,..

banjodeano

banjodeano

scouse

Hey deno
nice to meet you, glad we got yer bike running
congrats on getting the job
that's the way to do it summer off work over autum/winter

Gary T

banjodeano

Thanks Gary, great to meet you guys as well... nice to hear the noise and see the smoke of the KH....
it was a great day, opened a letter when you guys had gone and got a job offer.think i am gonna buy a lottery ticket this weekend...
Got a new battery coming from the company that sent the dud one, but i am still worrying that there is something else going on...
catch you later
Deano

BIG AL

Glad you got it sorted banjo with some help from scouse and gra , and nice to see you got a job

lets hope the luck rubs of on graham and he lands a job as well,
graham just called round and told me his interveiw went well, heres hoping gra
hope to see you at squires soon then banjo
god its boring at home second week off after my little incident and im bored shit less

cheers al

banjodeano

Thanks Big Al, Graham asked me up to squires, cant make it this week but will def show my face one day soon, hopefully on my triple... not the same turning up in a 307

Failing that i will get my mate to take me up on his Z1..

The Wolfman

Better Still there's a couple or three bike events this weekend for any one interested.

Hull, Hull and Ackworth.

Nice to meet you too Deano.

180kid

whats the problem with the boyer set up then ?,...

great news on the job...

The Wolfman

Dunno what the boyer problem is (if any), it wouldn't stay still.... (fooking thing kept moving the goalposts) at one point we were beginning to think that Boyer themselves didn't know what current their Ignitions take from the supply..

But the battery is definitely knackered and we'll start testing again once there's a good one to hold the voltage up.

It's also a bit awkward trying to start an engine in a frame propped on top of a crate of bottles, all waggling around..

banjodeano

banjodeano