GT250R won't start (but cranks)

**Sentox** · 21st June 2010, 13:25

First of all, apologies to the mods if this is in the wrong place. Not really sure what category it belongs under at present, and I was hoping more people might see it here.

Anyway, the basics: last rode the bike (Hyosung GT250R, EFI) on Saturday. No problems; everything running fine. Go to jump on it today, and it cranks but won't start. Headlights seem nice and bright, starter motor sounds normal and keeps turning over, so I'm thinking the battery is ok. It does the usual startup process: fuel pump primes - at least I think that's the loud whirring noise, I may be mistaken on this one - and the tach needle cycles from max to zero; no warning lights or anything out of the ordinary.

I've been trying to crank it every so often, and a couple of times it has caught after 5 or 6 seconds of turning over, but idles extremely lumpy (under 1k rpm) for a few seconds then dies again. On my last attempt to start it it wouldn't catch at all, and the tech needle was going a little crazy, which was strange.

I'm hoping someone might have some idea of what might be at fault. I've thought about checking the spark on someone's advice, but it looks very difficult to get at the plugs without dismantling a lot of stuff (if anyone who knows Hyosungs has any advice in this it would be helpful as well).

Thanks guys!

**MSTRS:Me** · 21st June 2010, 13:56

Your description of symptoms makes me think that the auto choke is not actuating properly. Or you've somehow flooded the engine...is that possible with injection?

**Sentox** · 21st June 2010, 14:05

One thing I didn't think of is that it has been outdoors (albeit with a bike cover) overnight. Usually it stays in the garage. Could condensation or such cause issues?

**CookMySock** · 21st June 2010, 14:12

The tach needle jumping around normally means theres a fault with the ignition pickup or associated wiring. Unplug the pickup and CDI and see if theres any moisture in the connectors.

Steve

**MSTRS:Me** · 21st June 2010, 14:38

Originally Posted by Sentox

One thing I didn't think of is that it has been outdoors (albeit with a bike cover) overnight. Usually it stays in the garage. Could condensation or such cause issues?

If that's the one thing different from normal (and you don't normally have a problem starting) then there may be something in what you say re condensation. It was pretty wet yesterday...

**MSTRS:Me** · 21st June 2010, 15:19

Any luck sorting it?

**Sentox** · 21st June 2010, 15:34

Originally Posted by MSTRS

Any luck sorting it?

Got caught up with some work at home, unfortunately, and soon I have to go and meet someone. I'm hoping I can get home early enough this evening to get stuck into it, otherwise I'll be getting up early in the morning to have a crack at it. I'm trying to wait until I have a few hours spare before I start unscrewing stuff.

**MSTRS:Me** · 21st June 2010, 15:38

Whatever it is, it will be something very simple. Diagnosing the fault is the hard part...because so many causes can have the same symptoms.

**wanpo** · 21st June 2010, 15:40

Tried push starting?
I've had problems getting mine (albeit carbureted) started on some mornings, I just keep away at it, giving it throttle when it catches, hoping I don't flood the engine, until it doesn't stall and revs up.

**imdying** · 21st June 2010, 15:51

Tighten your battery leads.

**Swoop** · 21st June 2010, 15:54

Check the label on the frame.
If it says "Hyosung" you will need to replace the bike with something more reliable.

**Sentox** · 22nd June 2010, 09:58

Checked battery leads, electrical connections, and spark this morning. Couldn't find anything loose or any moisture, and spark seemed nice and strong, so it's probably going to the workshop at this rate. Mechanic recommended I let it sit for a few days and go over the connections with CRC, so I'll do that and charge the battery, but otherwise things are going beyond my limited knowledge (and toolset). Unfortunately I don't have a way of moving the bike for the next fortnight or so. In my experience, it takes about three days for riding withdrawals to set in