hi im new here so firstly hello!,
my 1vj tenere600 wont start from cold at all.the story is...
i bought the bike as a basket case and have spent literally three years building it up in spare time.
only reliable way of starting it now is lots of easy start,fully charged battery,use leckky start button and hope for the best.when it fires hold revs up till it warms up.when hot its fine( well for a ageing 600 single)
its had;
bore honed-compression is v good but not totally run in yet
plug
valve clearences are correct to best of my knowledge
carbs have been apart and cleaned inc the tiny hidden filter
carb rubbers are old but i think there good
valves ground in and all top end overhauled.
timing is correct to best of my knowledge( it runs when hot ok)
standard exhaust fitted if a bit welded up etc due to its age

i belive its a fuel prob.plug is never soaking wet when removed but you can smell fuel.i am using the standard fuel pump.ive neard bypassing can be worthwhile tho never tried it (again it runs when warm) there is an inline fuel filter that i added before the pump.didnt know if this could restrict the flow to the pump?the choke apearrs to make no difference at all.when the bike is warm and idling ive pulled it out,presuming it would then be to rich and stall, but this doesnt happen.no change.have had carbs apart and looked in passageways, blown thro with an air line etc.seemed ok?
so im thinking mixture is really lean or rubbers are leaking or somethings wrong in the carb or fuel supply to the carb maybe??? only thing that gets me is its fine when hot???
what gets me is the total lack of starting, i mean its nothing not even the odd bang.nothing.and thats with the leckky start.with the kick you wont get anything at all.this is fairly true when hot too.kick rarely ever works.its start button or a push really.
pls pls give me some advice, ive spent so may long nights trying to find out whats wrong and ive fixed so many other things and other peoples bodges im so sick of it now.im sure that is actually just a simple thing and its so close to being spot on.cheers dan

to the HUBB.....
That sounds like a normal XT to me! ( nah only joking) a well set up XT should start second kick third at a push. even in cold!

my suggestions......

Lay off the Easystart. it can mask all sorts of problems. you dont want to be carrying that around all the time, they are made to run without it, so try not to use it.

Try a new properly gapped plug, you would be suprised what difference a new NGK can make. though I am sure you have already checked the HT stuff.

Dont even THINK about touching the throttle untill she fires, they flood easy! I have a kickstart only 1989 2KF and I keep the throttle closed till the second or the third kick, when she fires, open a quarter, let her settle then she will be ok.

failing that someone will come along soon and give some advice.

Martyn

Could be carb or electrical.

I presume that having had the carb out, you have reassembled it according to tuning spec.

Is the float level set correctly? 5-9 mm from top of float bowl

Is the pilot jet set correctly? +- 2 - 2.5 turns out

Has the cd slide in the primary carb been adjusted correctly to closed stop? about 1 - 3mm

Have you had the plug out and cranked her over to check how strong the spark is? And that it is sparking at the correct timing position?

ok thanks for replys chaps!
the bike is currently in storage as its too cold and missus has had enuff of the sight of it but from memory...
i did adjust what i belive is the mixture screw.it was under the bottom of the carb and i did it with carbs off (cant see how you could with it in situ?) yamaha said its 2.5 turns out (it was 1.5 and it improved things marginally)

plug is new and should be gapped ok
regards the spark.it has got one and it looks average??? what does a weak one look like??

regards timing.after rebuilding top end i was careful to put cam chain,gears and flywheel in line with all their marks.like i said it runs and i thought it didnt have minor adjustment ( would you use a timing light or something???)it was a pig before and after the rebuild so dont think anythings radically different.
regards the in side settings on the carb i pretty much didnt disturb settings but when it comes back to me next year i think i may need to re do the carbs and check everything.(the clymer manual i have isnt the exact same carbs as the 1vj so im never to confident in what i says.( any good sources for this info on the web or for a good manual??) the other thing with carb settings is i have wound up the knob on the idle speed so it warms up at idle with out cutting out.this then means it races when warm.where should this be set on average.presume the butterfly should be shut or virtually.

pls advise and once again i wish i had found these pages long ago!

Hiya Dan

Idle speed should be about 1000-1100rpm though mine likes 1200.

when cold it will always idle 'Lumpy' so i turn it up a bit, them adjust down when hot, Im not saying that is correct, just what I do with mine.... By the way mine is 1989 and has 37,800kms on the clock and had been used as a field bike for 2 years by two teenagers before I got it. ( so thrashed from cold , abused, neglected and was a scrapper when I bought it) but I have not touched the Engine. It uses oil, about a pint per 400km but im hoping that is valve stem oil seals. Always smokes a bit when cold, first 10 seconds, then OK.

Have you checked that the carbs are seated correctly in the rubber stubs? a smear of vaseline helps them to slide in. also make sure the stubs arent split or dont leak. ( the easystart is a good leak tester but i prefer WD40, as its marginally less flammable) if the carbs arent seated correctly it will be a PIG to start. Dont ask me how I know!

Have fun

Martyn

oh thats good then martyn, your has nearly identical history to mine.mine was stolen, half stripped sold for salvage, bought by some one with good intention who then bought a donor bike which had better prospects and stripped/became a rat bike whilst the other was built up to a good un! then sold as a runner(just) to a guy who then used it as a donor and i ( stupidly ) bought what was left. having never had a bi four before i went on to find out how expensive, rare and desirable the parts are, and how many of them were missing or had been swapped for the wrong thing! my saviour was a local guy i found who sold me a fire damaged one (only one ive ever seen local) which had all the missing bits i needed and none i didnt.if it werent for that it would have been sold long ago.its been annoying me for nearly three years and its got to the stage now where i will not part with it untill it runs properly.it i did id spend the rest of my days wondering what it needs....

am i right in saying i was quoted 50 quid for the carb rubbers or is that each?

BUT check them BEFORE you go buying new ones. sometimes if they are just leaking you can seal them.

ANSAUGSTUTZEN NEU MANIFOLD SET NEW XT600 XT 600 -´83 bei eBay.de: Oldtimer-Motorradteile (endet 20.12.07 13:58:10 MEZ)

ANSAUGSTUTZEN NEU MANIFOLD SET NEW XT600 XT 600 ´84 - bei eBay.de: Oldtimer-Motorradteile (endet 20.12.07 13:58:12 MEZ)

The first one is up to 1983 the second is 1983 0n. 44 euros the PAIR may even get cheaper if you scout about

Regards

Martyn

Well, it sounds like you have a good understanding of what you are doing and the effects you can have when you change something.

What I would advise you to do is read into some of the past threads on this subject; there are absolute shedloads about this engine (what does that tell us?!).
Use the HUBB search facility for keywords such as cold starting/poor starting/non starting etc etc, or just read back through this forum.

I suggest that you don't ignore the threads about the Yam TT600R; it has more or less the same engine.

Just make sure that the bike is fully serviced and everything is in correct adjustment, then make one adjustment at a time and make a judgement about what effect that had - change more than one and you don't know "what caused what".

BTW, 10/10 for persistance during these past 3 years!

Good luck,

__________________
Dave

I'm not saying it cannot be something else, but it seems to me that your choking / idle circuit is (way too) lean.
Apart from carb rubbers, the issue can be with:
- Choke system: in fact this is, on these carbs, an additional, primitive, very richly set 'additional carburettor'. Make sure that it gets fuel, and all channels in the carb body that serve it are clean etc.
- Idle setting: for an older bike, 2,5 turns out is not enough. Set it at for instance 4 - 4,5 turns out, making it richer and try again.
- General, but influencing choke and idle: float level: adjust as per earlier post.

Good luck!
Auke

__________________
Auke
http://aukemarieke.blogspot.com

people have mentioned the idle mixture settings and i said about what i belive is genereal fuel air mixture adjustment screw.where are these on the 1vj carbs as im not sure.as i said the one i adjusted was right under the carb and very hard to access when in situ

oh somewthing else ive remembered and dont know if it relevent.when bike is warm and running at idle it will occasionally mis fire slightly and make a loud noise.a kind of squeak.sounds weird but the best way to describe it is its like when a dog sneezes.weird i know but it exactly like that.like a rush of air,suddenly squeeking????

C'mon Aukeboss! you must have an answer for this one! ( cos im dying to know...)

Martyn

Just in case you think im taking the mickey, im not, i went straight out and with a cold engine readjusted the mixture screw on my XT600 as per you instructions ( mine was 2.5 turns out too) it is now 4 out. STARTS 1st Kick.... Ta!

Oh wow that is weird
My guess; and this is only a stab in the dark: You're getting blowback into the crank case

If this is the case it may well be worthwhile to check that you are not running too rich even though the inclination here seems to be you're too lean. Especially in light of the fact that you say the choke doesn't seem to make any difference.

In the exhaust/silencer?

__________________
Dave