Srx hard to start when warm

[Danxup]

Ey up..  ive recently purchased a srx600. it starts prfectly from cold usually second kick.. runs sweet.  rides sweet...
But ... she is an absolute pig to start when hot.... could anyone help please.. many thanks
Dan..

[themoudie]

Aye Dan,

Welcome to the forum, others maybe along to chip in their pennies worth; here's mine for a start.

I have a 1986 SRX600 'Sally', don't ask    and starting was a bit hit and miss, cold or hot. I suspect that the hot starting problem is due to the fuel in the carbs evaporating due to the heat after a good run. Or else the coil insulation may not be liking the heat and breaking down, but I think that this is unlikely. Sally sometimes 'dies' after a good long run, with fuel starvation, inspite of the tank breather being clear, the cure is to switch to 'PRIME' on the fuel tap and then revert to the vacuum 'ON' position. If your vacuum hose is old and perished, its replacement, maybe the easy fix.    Also, try priming the cylinder with one or two gentle kicks, with the ignition 'OFF', this helps ensure any loss to evaporation is avoided. But beware, you may get a cracker of a backfire, when you turn the ignition back 'ON' and give the motor a good swing! 

I would suggest a check of the air cleaner and fit a new one, if necessary. I'll leave the choice of OEM or equivilent to you. Maybe fit a K&N, as I did 12 years ago, although the current price is horrendous, they are fit and 'forget' (almost), and being washable last the life of the bike.

Check your spark plug and renew if at all in doubt, I use an NGK Iridium plug (DPR8EIX-9 Iridium), again they are no cheap, but fitting one made Sally easier to start and smooth running.

Check that your choke plunger is not siezed in its bore and that the whole mechanism is free to move, including the cable. They often come out looking like a good Thai red curry sauce if the water has got in and started to corrode things. refurbishment parts kits are obtainable from NRP (NRP_link) or Wemoto (Wemoto_link).

Check that the fuel filters in the bottom of the petrol tank, carburettor and any supplementary ones fitted in the fuel lines are clean.

Check your valve clearances, they may be "tight" when the motor is hot, adjust if necessary.

And check that coil, just in case.

The other thing to check is the generator as this supplies power to the ignition, regardless of the condition of the battery and if the shellac is startinmg to break up on the coil windings with heat, this maybe another problem. But, as I have said before, I would check the fuel side of things first. Sally is now up to 120,000Kms and seems ......  

If you need a workshop manual, I can supply a reasonable pdf copy FOC. Private Message me with your email address, via the forum and I'll send one across. The PM link is on the left side of the message window, below my avatar.

I hope this helps.

My regards, Bill

[Danxup]

Bye eck bill.. thanks for all that info... very much appreciated.
Ill let you know how i get on.. mine is also a 1986 its in decent order other than this problem.. thanks again.. ill message you for the manual too thats ace!!

[Steve Lake]

Hi Dan, welcome to 'the madhouse'....
I have owned 7 srx6's.... currently 3 in the stable, & only one 'on the road' at present.
only ever had one of them that had your problem (though it is a well recorded issue on these bikes)
Bill has pretty much covered all the angles, I'd certainly put them in the order of 1) Fuel. 2) coil. 3) generator breakdown.
you really need to strip out the fuel system, from tank to inlet manifold... clean and/or replace anything that looks 'iffy', and if possible get an air line onto the carbs. the fuel tap can be an issue, but as Bill says running it on 'prime' in effect bypasses the vacuum valve.
(you can get a service kit for these taps, but beware... my Son got a kit for his SRX, but it appears it's already failed and is probably cheap crap not up to dealing with current fuel technology).
Coils can be obtained, but a bit pricey.... I have a working spare which you can borrow as a diagnostic tool should you wish.
Generator... only way I've ever tested this is just to take the plug out and kick the motor over and look for a spark ( this is huge fun to do when the engine is stinking hot after a good run :-) ), I do have an oscilloscope, which can show the size & duration of the power pulse from the generator to the coil... but not the power of the pulse.
not sure where you are Dan.... I'm near Norwich... if you're within marching distance bring the beastie round here ....
good luck
Steve (L) (we have a few Steve's lurking in here  )

[Danxup]

Now then steve.. im up in west yorkshire near wakefield im affraid .. thanks for the tips ill start with the fuel then and work my way round.  Much appreciated.. a trip to Norwich might be in order if i get stuck 🤐 i have a 87 400 that has the opposite problem takes abit to start but once warm fires firts time evry time.. are the coils the same do you know ? I could swap some bits about .. cheers steve!

[themoudie]

Aye Dan,

Manual on its way!

As for the 400 being a slouch to start when cold. Try the priming technique mentioned in my first post. Fuel tap to 'PRIME', full choke, 2 or 3 easy swings through the 4 stroke cycle from TDC, then switch the ignition 'ON', and with the piston just eased over TDC, give it a lusty swing. DO NOT OPEN THE THROTTLE! Once running, apply only a smidge of throttle and ease the choke to the halfway position (there is a positive stop on the lever) and warm the motor through. With Sally I usually get underway at the half choke stage and then use small throttle openings to warm the motor through, whilst going up through the gears. Knock the choke 'OFF' after a couple of miles and apply throttle! 

Also, don't 'lug' the 600 in 5th gear, it is a known weak point and the torque will strip the teeth from the gears and or pit them severely.    This results in a complete engine strip to replace the offending gears.    I would advise that you don't select 5th unless you are doing at least 50mph - 55mph, with 3,000rpm plus. I apologies if this is all familiar to you, but I thought that I should mention it, just in case. Both SteveL and I, along with others have had this problem to sort out.

My regards, Bill

[Steve Lake]

Spot on Bill, as you know, #1 SRX6 is still in the waiting room, in the queue for a gearbox repair ... hopefully get it done before the anniversary of the 'crunch' which was August bank holiday ... on my way to Wimbotsham classic bike show.... difficult to apply my mind to it when #6 is looking so good and going so well  ....
pip pip

[Danxup]

Cheers for the advice on 5th gear.  The bloke i bought it of said it had had a full rebuild 2000 miles ago due to the 5th gear thing... ill bear it in mind when out scratching..
Ill let you all know how i get on . 😁⚡⚡

[themoudie]

Aye Steve,

"Sally" all ship shape again after the collision, just waiting for the leg to be able to cope with turning her over!   

"Gert" the SRX Mono is taking up the time, along with the Duke 450, and the weather hasn't exactly been conducive to getting my confidence back again.

Just make sure that tank and the carb haven't any rank fuel left in them, or else you may have another expensive job on top of the engine rebuild. 

Good health.

My regards, Bill

[Moto63]

[quote author=themoudie link=topic=9253.msg65488#msg65488 date=1525379338
the weather hasn't exactly been conducive to getting my confidence back again

Good health.

My regards, Bill
[/quote]
Stick with it Bill, it'll come. Best o luck....keep doing the physio💪
Cheers, Michael

[themoudie]

Aye Michael,

What physio? NHS hasn't any capacity up here and the surgeon said "You know what to do, crack on!", so it's down to self help and bl**dy mindedness.  Walking up to 4 miles a day and doing one leg squats seems to be doing the trick.

Starting a recalcitrant SRX will either make or break it, hopefully not the later! 

May I ask if you have been on tour yet? PM me if you would prefer.

Good health, Bill

[Moto63]

Evening Bill, when you say "tour" I assume you mean our Moffat long weekender??.... no mate it's all booked and we're raring to go but alas we'll have to wait until back end of august. The buccleuch arms was well booked up. Get in with the booking earlier next year has been the cry.😉.... regarding the physio, I ended up paying for some sessions as the NHS thing was frankly a joke. It was money well spent I must say. Yes keep walking, I did quite a lot of that as I wasn't allowed to drive for 6 months due to the brain injury....had to surrender my driving licence, oh and yes..I too was surprised there was enough in there to injure 🤣🤣🤕
Stay focused and best of luck... cheers, Michael

[themoudie]

Are the Buckluck Hotel, that place can tell a few stories and I'm pretty sure I was leaving as you came down for breakfast the last time you stayed. That was afore my retirement. If you like your Indian, have you tried the wee one opposite? 

As for the grey matter, I would never cast such aspersions about a fellow 'Thumpeteer'!   

My regards, Bill

[Danxup]

Im sat at the side of the road with the 600.. first time ive took it on a decent run since i bought it .. i thought ill have a run out and then when i get back and its hot ill start looking for problems... the bike was going great .. but then the fuel starvation thing started to happen.. i switched to prime while still riding but eventualy she cut out .. waiting for aa.  I think shes gonna get thrown in the garage till next week the weather is so nice im going to go out on the 400

[Steve Lake]

that's a bu55er Dan.... next time it happens, try opening the filler, might just be a vacuum building up if it's not breathing properly, still ...lovely day to be sitting in the quiet listening to nature going about it's business.....