I think I may have been naive with sparkplugs.

Hi Guys!

Posted a little while ago about an intermittent misfire in one of my cylinders causing idling problems. I still havent been able to get to the bottom of this I had ruled out sparkplugs as causing the issue as the first thing I did was put in new ones, however, last night my driving instructor told me that when you put in new ones you have to adjust the electrode gap according to what it says in the manual. I didn't, I just bunged the new ones in... Which didn't solve the initial problem. Was my driving instructor correct? Could this be the problem?

All input welcome!

Thanks

Chris

[yorkie_chris]

I always check, but I've never had to adjust an NGK for the SV.

[Scoobs]

They normally come correctly gapped. I'm like Yorkie Chris. Always checked the gap with feeler gauges, but never had to adjust.

Its a good idea to check them in case they have taken a thump at some point, but the gaps come pre-set to a reasonable gap. I never check them properly, just look at the gap by eye ... I've seen enough to know if they were a mile out

You may have just been unlucky and got a dodgy new plug (had this happen before) .. however, if you have swapped the plugs for new, then I'd suggest looking at the coils! ...

Do you have a mate with an SV that wouldn't mind you swapping coils quickly?

[yorkie_chris]

Have you done resistance check on coil and leads?

(not fool proof, but a good start)

Thanks for the reply guys, no haven't checked the coils, mainly because i'm not really sure what they are or what they look like! my dealer (bike) told me that if it was the coil the cylinder wouldn't work and all, however, it's intermittent. All he did was sold me some petrol additive to flush through... are the coils easy to check for a novice? Where actually are they!?

Chris

Originally Posted by poisonidea

Thanks for the reply guys, no haven't checked the coils, mainly because i'm not really sure what they are or what they look like! my dealer (bike) told me that if it was the coil the cylinder wouldn't work and all, however, it's intermittent. All he did was sold me some petrol additive to flush through... are the coils easy to check for a novice? Where actually are they!?

Chris

Just follow the spark plug cap back, there is a bit of lead and the coil ... to be fair, the problem could be in the cap, the lead or the coil ... or even simply loose connections to the coil from the loom.

D/L the manuals from the main site and have a looksee in there

Oh and coils can have intermittent faults your dude is talking out of his behind!!

Originally Posted by yorkie_chris

I always check, but I've never had to adjust an NGK for the SV.

+ 1

It could even be HT lead break down causing it to be intermittant (I know Petevtwin650 had this issue on his curvy).

The HT leads can be taken apart at the cap, crimped nicely again, and put back together to give a better connection.

[yorkie_chris]

Your dealers talking out of his rse.

Coils can be totally fine off the bike, check out fine in resistance, spark fine off the engine but when you try use them at full throttle the extra load from a denser fuel-air mix means they can't handle it.