Plug fouling, hard starting, backfiring & intermittent smoke

[Russ]

For the first time in almost 5 years & 26,000kms my 630 is giving me grief. Until now it's always fired up first thing, but it's now failed to start on two occasions despite strong cranking. The culprit has been fouled plugs, which has been accompanied by loud backfiring when turning over, so sounds like a fuelling issue. I got it going again by fitting a new iridium plug (again a loud backfire, but then started & going like a rocket). It's since been at the dealers for a month for a service & fixing the damned air box cover. I collected it today & it again failed to start, this time outside their shop just after I paid them the $2K+ service bill... So they wheeled it out the back, noted it had fouled the new plug & got it running again. It's now home, but I have no confidence it'll be right.

The dealer said that when they changed the oil it contained a lot of metal from one of the oil screens perishing. It has also started blowing smoke intermittently - a heap of it, then nothing. I wonder whether it's all interrelated, but I'm fast losing confidence in it as I ride in remote areas by myself & can't have an unreliable steed. I'm strongly considering selling it & getting a 701, not that I want to as I otherwise love the 630.

Any ideas as to what's going on with it? It does have a JD kit, but that's been on for 4 years without issue & I haven't changed anything on the bike mechanically or usage wise.

 

[RDTCU]

Fouled plugs and smoke could be a bad valve seal or piston rings...

 

[rickcj7]

When my oil screen fell apart lots of metal shavings got on the crank sensor and ruined it. Was hard to start for a while and then just wouldn't start at all.

 

[DYNOBOB]

Compression and leak down to rule out mechanical issues.

Do you have access to iBeat to check for codes?

Symptoms sound like TPS/BPS/IAT sensor could be going out.

Maybe try a new coolant temp sensor.

.

 

[Russ]

Thanks for the tips gents, and no Bob, I don't have Ibeat.

I took the bike for a 90 minute run today. It started well on several occasions, blew no smoke at all and ran as strongly and cleanly as it ever has. It's puzzling that it can run so well yet fail to fire on other occasions.

 

[DYNOBOB]

I took the bike for a 90 minute run today. It started well on several occasions, blew no smoke at all and ran as strongly and cleanly as it ever has. It's puzzling that it can run so well yet fail to fire on other occasions.

That's a good sign, means you don't have a mechanical problem. More than likely it's one of the sensors I mentioned. Had the bike gotten really wet lately? That's often when the TPS issues start.

.

 

[Russ]

Had the bike gotten really wet lately? That's often when the TPS issues start.
.

Hmmm, interesting. I did wash my bike with one of those Gerni pressure cleaners after the last ride before the starting problems commenced, although it was blowing smoke before that. I usually steer clear of these washers as I'm wary of them blowing water into electrical areas, so thought I'd been careful enough to stay a fair way back and keep it to the motor, guards, underside of bike etc. I wonder whether this may be it, particularly as I think the TPS sensors have been a problem generally with a few of these bikes. Where is that sensor located?

 

[mekanik]

Left hand side of engine on throttle body. On mine the problem area was the connector itself, I had to take the connector apart. It was dry on the outside and the tps was dry, the connector was completely full.

 

[ghte]

Hey Russ is that your 630 for sale in Manly-similar kilometres

 

[Russ]

No Glenn, mine's not for sale. Since bringing it home from the dealer it's been starting easily and running strong, clean & hard without any hint of smoke. I'll keep it so long as things stay this way, if not I'll look at a new bike like the 701 or even the Beta 480.

How long have you had the 630? What do you think of it so far? What type of riding are you doing with it & where? Certainly a lot different machine to your 310! I usually head out once a month of a Sunday with another rider or two if you're interested in some company.

 

[ghte]

Hi Russ, I have had the 630 about 2 weeks. I was looking for one and could not find one at a fair price or that was not in Perth et al. I went to Muswelbrook with a mate to look at a KTM 690-it was not as represented in the photos so I passed. On the way back to Sydney I popped into Cessnock KTM to scout a second hand 690. They had none, but would you believe it they traded a late model 630 the day before with only 750 kms on it for a KTM 250. The owner decided he wanted to go serious bush with his mates. It has a Tourtech rack, Barkbusters, Arrow pipes,B&B bash plate all mine for $6,500.
Only ridden her once on tar, she feels well sorted and tight. We are in the midst of packing to move to Bright this Friday. The 630 fits nicely between my 310's and my road bikes for that part of the world.
All the best Russ and PM me if you are down that way I will show you some rip snorting 630 rides

 

[motranqui]

. Since bringing it home from the dealer it's been starting easily and running strong, clean & hard without any hint of smoke. I'll keep it so long as things stay this way,

Did the dealer tell you the reason why the bike had those problems?

 

[Russ]

Hi Glenn, that's an absolute bargain with those kms & accessories. He probably spent ~$15K with the $2K pipes, so one of life's rare wins!

If not already done I would strongly recommend:

1. Strengthening the rear sub frame - it will break if you carry anything remotely heavy on the rack (mine did twice, including once after reinforcing).
2. Installing a JD Power Tune or Power Commander - the JD I installed cost only ~$250 and resulted in a significant improvement - much more enjoyable and aggressive ride, but caution not to set it too rich (wastes fuel & stutters a little).
3. Seat Concepts Seat - fantastic value improvement at less than $300.
4. Better foot pegs - the OEMs are rubbish - too short & skinny.
5. Rim locks front & rear.
6. Heated grips for Vic high country!
7. Air box nut fix, otherwise it'll continue to drive you crazy not being able to perform this most basic of maintenance.
8. Keep an eye on the metal oil screens - mine perished & ended up in the oil.
9. Same with clutch cush washers - reports of these being too soft and perishing.
10. My Arrows came with DB killers which I only just fitted after 4 years - made it a little quieter without any noticeable performance loss, so I'd recommend doing this if you have them & they aren't already fitted.

That's about it. They are a terrific bike, you just need to put up with a few niggles but it's well worth it.

It's a shame you're leaving Sydney as I'm sure you'd know a lot of tracks in the surrounds. All the best for the move to Bright - some terrific riding down there.

 

[Russ]

Did the dealer tell you the reason why the bike had those problems?

No, they didn't know. It had the symptoms on the last ride before the service. The dealer had the bike for a month trying to fix the spinning air box nuts, then in the last few days changed the oil and found the metal filter remnants. After they flushed that out it was ready to go, but when collected it from the dealer it wouldn't start. So they took it back inside, un-fouled the plug and got it running again. They suggested I take it home, ride it and "see how it goes". So far so good, with no starting or smoking issues, but time will tell.