GPX250RR Problem

[The Pastor]

yeah man, give it a good 5-10 mins to warm up, be gentel on your bike.

EDIT: We used to put hot water bottles on the carb overnight when cars did this back in the day. You could try that. Some folk used blankets. (Yes, I am serious)

yeah my mum had a 70's mitzi lancer once, we used to put a sheepskin on the engine over night to help it start in the morning.

[T.W.R]

So what your saying is everything is per normal until you put it into gear then release the clutch to take off then it dies ? then try it again and alls OK ?
It starts OK, idles Properly (around the 1000rpm +/- 50rpm), the choke works properly, it runs & performs normally ?.

Could be a weak spark possibly & if it runs fairly normally, then it may be deteriorated plug leads (H/T leads) breaking down under initial load occasionally, if their hard & stiff to bend then ditch them for new ones.

Otherwise it sounds like the clutch plates are partially binding & being a smaller capacity engine its enough to stall the bike. Change the oil to the specified viscosity, 5w-40 is too light of oil for a older GPX250 and from that the clutch isn't being lubricated properly

[gamgee]

so what weight should i be using? i've got some 15/40 non synthetic would that be good?

[inlinefour]

take it to a mechanic

Finally some good advice from the GPx killer himself. Sounds like the lad has learnt? gamgee I do not believe you have a problem, apart from the fact that the bikes not being allowed to warm up properly. I have a old z50 that does exactly the same thing that you have described with your GPx. It allways comes right once the little engine is warm enough. Give the GPx a tune and then allow however long your bike needs to heat up to where its running good. The z50 takes at least 3 times longer to get heated up to a point that its happy to run. Used to also happen to one of my little xl100s bikes and the problem was resolved by sorting out the timing.

[SwanTiger]

I had a similar problem with one of my dirtbikes and occasionally (on really cold nights) encounter the same problem with my Hyosung.

I've found a quick amount of throttle action clears it up, usually getting 4,000 revolutions then dropping off then bringing back up again (for 2 seconds at a time) gets things running smoothly. However, I'll only do this if the engine is warm.

Otherwise its choked to life.

When was the last time you cleaned your carbeurators?

if all else fails take it to a mechanic

That's rich comming from someone who has "Motorcycle Mechanic" as their Occupation in their profile and can't fix their own bike.

[SwanTiger]

This is a website I sourced when I did a little research on Marks bike to familiarize myself with some of the common pitfalls and 'functions'. A very informative website and certainly worth browsing through.

http://faq.ninja250.org/index.php/Main_Page

[gamgee]

When was the last time you cleaned your carbeurators?

never
i've had it for what? must be about 6 or 8 months now so yeah i'll do a big tune up clean everything out change the oil and filter, check the timing, (i've got the owners manual) and whatever else i can think of...
damn speedo stopped working last night too, i'll have a look at that eventually as well, tacho etc still working fine
stupid thing is it's got all these wee niggles but once it gets going it runs like a dream, so yeah thanks guys

[skidMark]

That's rich comming from someone who has "Motorcycle Mechanic" as their Occupation in their profile and can't fix their own bike.

i ended up fixing it in the end stop your jaw flapping shit

[JimO]

winter in Dunedin...HA bloody Aucklanders how cold do you think it gets here 30 below jeez havnt had a proper winter here for years

[gamgee]

the year before last we had a proper winter, it snowed just about every week between mid july and mid september
got the speedo cable fixed... well plugged back in if you can call that fixing it

[Gixxer 4 ever]

We have an 02 Zuki DR 250 for farm work. It has the same problem. You need to give it more time to warm up. The DR is doing as you have described.
Even at work the oil cooler is taking the temp down soon after you stop it at work and with in a few minutes you have to warm it up again. I will remove it and plum a line from the inlet to the out let for the winter. Not something you should do but you don't have a problem as far as I see. Be patient