SV650S Engine Problems (unusual bike for the HUBB but I need some advice)
 

Hello.

As this is a fairly long post, I’d like to say thank you in advance to anyone who takes the time to read and respond.

My current bike is not what would be considered a ‘travel bike’ by the HUBB’s usual standards—it is a 2001 SV650S. I’d also like to mention now that although my knowledge of motorcycle mechanics is pretty low, I’m trying to improve as quickly as possible.

The bike started misfiring about a month ago and has been in and out of the garage ever since. The previous owner had made quite a few modifications, mainly a custom air filter and changes to the jetting.

It ran well for two years but has recently become a bit of a money pit.

It underwent a massive service that cost around £450 about three or four months ago but since then it has cost even more.

The first issues (after the big service) were general electrical faults, for example the fan switch needed replacing as the fan was not activating, causing the warning light to display. Shortly after I’d had this replaced, the bike started bogging down at high speed and misfiring. The carbs were cleaned out and the aftermarket air filter’s intake was reduced with a piece of plastic.

This fixed the problem for a while but then one day the bike refused to move at all. At first it ran but not at all smoothly and this deteriorated rapidly until there was a horrendous clattering sound that I think was being produced by one of the cylinders(?). Needless to say it went back to the garage.

The garage said there was some issues with the contact points and the ignition system and replaced some parts. They also adjusted the jetting as they said the bike had been running very rich.

Getting the bike back home from the garage after this work was an ordeal. It was a very warm day but it still took about five minutes on full choke with high revs before the choke could be released and the engine would idle without cutting out. About halfway (one mile) home it developed a misfire and was bogging down as soon as I got it up into second gear. I pulled over several times and gave it some revs in neutral and both cylinders ran smoothly although it popped a lot under high revs. I did this several times but in the end had to nurse it home in first and second gear. This tortured journey took about fifteen minutes and the engine was certainly warm enough to run under normal circumstances.

When home, I left it running for several more minutes and the engine seemed to level out so I took it around the block. It was suddenly running well, no bogging down, both cylinders firing etc. however under deceleration there was a lot of popping. As I understand it, this can be caused by running too lean. I’m taking it out tomorrow if possible to see if I have a repeat of the last trip. But even if it runs okay (as in it does not develop a misfire or any power-loss) it’s going back to the garage on Monday because the popping is very annoying and is now a constant feature of deceleration.

Now the main point of my post; I’m leaving the U.K. around the end of July. I would dearly like a new motorcycle (an XT600/DR400 or something of that ilk) but can’t really afford one without spending almost all of my travel funds (which are almost non-existent anyway) so I was planning to just take the SV. However if I get it abroad and the problems start again I could be in trouble.

I don’t intend to return to the UK so whatever bike I take needs to either last, or be sold abroad to fund a replacement.

So, after all that, here are my questions:

A) What do you think the issues could be with the bike? Is it something I could cope with given a Haynes manual and a tool box?

B) Considering these issues, should I take this bike, or (as costly as it may be) try to replace it?

C) If I do take the SV, how easy is it to sell a bike abroad if I need to ditch it? (I will be in or around the EU for the next couple of years as I need to be somewhere I can find work if and when I need it.)

Thanks again for taking the time to read my post.

Cal

Hey dude
OK - well so long as it was running OK when you got it, the mods aren't, in themselves, the problem...
Often the way with an older bike if you can't fix it yourself...
Common problem that sort of thing.
That's a really weird thing for them to do, given that the jetting was right for the filter and exhaust -if it was suddenly running too lean, that would mean a new fault, not that some magic had happened and suddenly the jets had changed size in the night.
Hmm. Sounds like a bodge fix to a symptom of a problem, rather than actually fixing the problem itself...
What points? It's a CDI ignition, no points. Maybe a problem with a pickup coil, that could cause a high engine speed misfire. In fact, my DRZ currently has that exact problem in Mongolia, but that's another story... No surprise it was now running very rich, there's a plastic restriction in the inlet of a bike that was previously jetted correctly!

Sounds like they'd ended up setting it up too lean.
Interesting - I think maybe you have an intermittent intake air leak, which when it's leaking leans out the mixture (hence them putting a restrictor in the inlet as a bodge) and when not leaking, richens it back up again. If they'd leaned off the jetting, it'd then run properly with the restrictor so long as it wasn't leaking, but when extra air was getting in it'd be far too lean.
Yes, but on the over-run (closed throttle) it's likely to be an air leak into the exhaust, I don't know about the SV, but on the TL1000S and TL1000R there is a gasket in a joint between the rear header and the rest of the exhaust system that fails and causes this exact same problem.
Fair enough, let us know how you get on....
Intermittent air leak into the intake (inlet rubber between carb and cylinder head, leaking scottoiler install, balance pipe perished (if there is one, I don't know for sure on the SV)
Only you can answer that question as it's about your piece of mind. To be honest, I'd be more interested in changing bike workshops than changing bike, right now...

Hello.

First, thanks for the in-depth and considered reply, it's very much appreciated! Gives me something to say to the garage and tells me where I need to do some reading!

Took the bike out on Sunday and then took it back to the garage on Monday.

On Sunday the bike fired up fine. Still popped on deceleration however so I decided to return it on Monday.

Monday morning however was a nightmare. Fired the bike up and it ran well in neutral so I let the engine heat up for a good five or ten minutes before setting off to the garage. As soon as I got into second gear the bike bogged down and really struggled—didn't even make it to the end of the road! I put it back in neutral and gave it some revs, it ran fine so off I went. Exactly the same thing happened; travelled about 100 metres and the engine began to struggle. It was like this all the way to the garage, it seemed to gradually get worse as the journey went on.

Nothing really changed between Sunday when it was OK and Monday when it was playing hell. The only difference would be the weather, the bike had been outside and it had rained on Monday but been dry on Sunday.

I'm in Scarborough at the moment, but moving down to Rotherham to visit my family before leaving the country near the end of the month. If the local garage get the bike working before Saturday then I'll be riding it down to Rotherham where (if it's still griping) I'll take it to a garage down there or perhaps just try working on it myself.

I really want to learn how to service a bike fully myself—precisely because of how awkward (and expensive) it is when you're relying on garages! But that said it doesn't seem like an ideal problem for a beginner so I'm going to have a think about whether or not I'd be best off leaving it to someone more experienced on this occasion.

Cheers!

Cal

What's new—
 

Caught a train up to Scarborough to get my bike back from the garage yesterday.

They said that they'd replaced the custom air filter with a standard one and been through and checked all the electrics.

Bike seems to be running OK. Ran fine on the journey back from Scarborough and fired up well today.

The bike is still popping on deceleration—not as often but it's still happening.

The reason they gave for this is because the bike has an aftermarket exhaust fitted that was put on whilst the bike had a restrictor kit and that kit has since been removed. I'm a little skeptical about this reasoning however as the restrictor was removed months ago and it ran fine with no popping for a good while after that before all the problems started. The popping only started AFTER it had been to the garage with the power loss issues so I still feel its probably something to do with the fuel mixture.

But the bike is back, it's running, and it won't be going back to that garage as it's a good 80 miles away from where I am now.

It's also running well enough for me to feel comfortable using it to travel.

Full summary then:

Bike has standard air filter.
Bike has jetting set up for the standard air filter.
Bike has aftermarket exhaust which the garage blames for the popping (even though it didn't pop before it went into the garage).
Bike is running well besides the occasional popping under deceleration.

Cal

Has it got an inline fuel filter? Perhaps the lean running is due to crud / rust in the fuel tank blocking the tank filter, and / or the in line filter.

If it has an in-line filter, replace it. If not, it might be wise to fit one.

Have a good look inside the fuel tank with a very bright torch, and see if there's any debris or corrosion in there.

Be interesting to know if there was anything in the carb bowls too.