Motorcycle filter: Will I ruin my bike if I ride it with these problems?

June 16, 2013 9:54 PM

I just paid $650 to have the carbs cleaned out on my 4-cylinder Honda Magna (94). They also found rust in the tank so they said they fixed that. I picked it up tonight and it's running terribly. It feels like it has the wrong gas type in it. One (or more... all?) of the cylinders is kind of knocking or just being loud, it feels like it can't hold an idle, when I shift into gear it feels like I'm lugging the engine. I have to give it way too much throttle to even get it into gear. I don't know what they did to mess it up, and I intend to have a word with them when they open again on Tuesday. (I mean, did they even test it after they put it back together?) In the mean time, tomorrow is Monday and I need to get to work. Could I potentially break things or mess things up further if I try to ride in? And what is the protocol on bike repairs. My feeling is that they've messed it up--I paid them $100/hr for the work because I trusted that they'd do a really great job. They didn't, so they should take responsibility and fix whatever they broke for free. Am I wrong on that?
posted by brenton to Travel & Transportation (12 answers total)

If it were my mechanic, I'd expect them to re-do the repairs on the carbs and tank for nothing. I expect the mechanic to test-ride it and return it in a fit state to ride. If they find that it's another problem entirely, that might be a different story, but they should be prepared, as you say, to fix their own repairs for free.

I'm a bit concerned when they said they 'fixed' rust inside the tank. Did they give you some idea of what the 'fix' was, did they shake it with bearing balls and CLR, or some other kind of cleaning? It might mean simply that they put some kind of additive in the fuel, or just cleaned the petcock filter. I'd definitely want more information on that part.
posted by Fiasco da Gama at 10:12 PM on June 16, 2013 [2 favorites]

If it's running worse than when you took it in, yes, they ought to take care of it. (This is why I put everything like this on my credit card instead of paying cash/check; if I do not get satisfaction, it's time for a chargeback.) The only really safe step is not to ride it until you can have it looked at again. There's no telling what they did to it. Maybe they got the mix way off and it's running really lean, which is bad. Maybe they damaged a jet or left debris behind or damaged a float. It's impossible to tell, but not worth the risk. Can you bum a ride or take a taxi? If you do ride it, knowing that it's not running right at all, and something does fail... I don't see how the shop ought to be liable for that.
posted by xedrik at 10:13 PM on June 16, 2013

Response by poster: I'm a bit concerned when they said they 'fixed' rust inside the tank.
I didn't catch all of what he said when he explained it, but it was something like flushing the tank with a liquid, letting it dry, flushing it again, etc. But I can't quite remember exactly what he said.
posted by brenton at 10:15 PM on June 16, 2013

It's been years since I had a bike and I'm sure someone will come along with a more solid answer, but to me it sounds like the fuel/air mix is way too lean. It could be that they didn't adjust it and didn't test it, or that they damaged something and there's a new path for air to get sucked in. It could also simply be that the fuel filter got clogged when they did whatever they did to the tank, or if they coated it that some of the coating is clogging up the fuel flow.

I have to ask - you're not out of gas are you?

In any case it sounds like they didn't test it or they would have noticed.

I personally would not ride my bike if it behaved that way until I got it fixed for real. I don't think it's super-likely you'll damage it but I think there is a possiblity (again I've been out of the motorcycle world for a while so this is pretty much conjecture on my part). But I'd also be worried about the bike dying on me at a really inopportune time, or not being able to accelerate when I needed it most.

As far as whether the shop will take responsibility, that really depends on the people who run it. I had a guy who didn't torque the bolts on my front brake assembly and it came off when I was riding it. He also damaged my front fork when he replaced the seals. He tried not to take responsibility but I threatened him with a lawsuit and a storm of bad publicity and he ended up refunding my money and buying a new fork tube for me. I've also had car mechanics who have blown me off when their repairs were inadequate. It depends on how much they care about their reputation and whether they think you'll escalate or take some kind of further action against them. But in my opinion they definitely should make it right at no charge, and if they were really decent people they'd pay for a day or two of car rental until the bike was back up to snuff.
posted by under_petticoat_rule at 10:15 PM on June 16, 2013

Also, you didn't ask, but you can learn to clean your carbs yourself and save a ton of money. It's kind of daunting and seems complex until you learn how, then it's not that hard provided you have some degree of mechanical aptitude and manual dexterity.

I used to clean the carbs on my '82 Silverwing. The hardest part was getting them off the bike (and back on too). There are some small parts you want to make sure you don't lose, and you have to be careful, but it's not that hard. Mine didn't require any specialized tools.

You do need someplace like a garage or well-ventilated basement to do it because the cleaner is pretty stinky. Also neoprene gloves, and eye protection.

Get a Clymer manual for your year and model, it will have all the steps with pictures. Once you have it down it'll take less than two hours and you can spend the money you save on something more fun, like new tires or a sweet leather jacket.
posted by under_petticoat_rule at 10:27 PM on June 16, 2013 [2 favorites]

I think the protocol for repairs is "fix it." They didn't.
posted by oceanjesse at 10:38 PM on June 16, 2013 [1 favorite]

No, you are not wrong.

The mixture is off. Sounds like it may be too lean, and if that's what's going on, the bike will be running too hot and may even seize. Once that happens, it'll be a whole lot more broken (and you may be, too). Plus, by then it'll be impossible to see whether or not they did anything wrong.

Don't ride it, please. As I see it, your steps are:

- Take it back
- Ask them to fix it so it actually runs well. You should not be charged again for this.
- Ask what they did to the tank again, you just need to know. Did they put a coating in?
- Get a Clymer's and learn how to clean and replace stuff on the bike yourself. It's incredibly rewarding and gives you a deeper level of ownership.
posted by Too-Ticky at 11:47 PM on June 16, 2013

I wouldn't be concerned about causing any real damage unless it was running lean(which sounds possible), but i also wouldn't ride it. I've been in a very similar situation with the carb on my car.

I'd be most concerned about the improper mixture fouling a plug if it was running rich, or otherwise creating a situation in which it was stuck on the side of the road halfway to work, in the parking lot at work, halfway home from work, etc. And fuck that. The problems running lean could cause are obviously much worse, up to pretty much requiring a full engine rebuild and overbore with new pistons and such. There's some overlap in how running rich can sound/feel vs running lean, and the description you gave kinda covers both.

Personally, i'd call a cab too and from work and bring them the receipts. Tell them you couldn't ride it to work because they hosed their repair.

After they fix it or refund you(there is no option here in which they should be charging you anything but $0, or -$650) never go to that shop again.
posted by emptythought at 11:55 PM on June 16, 2013

Yes they should have carried out the work and tested it and returned it in working order. If you would like me to guess the problem I would go for an air leak resulting from having to disturb 20 yr old carb rubbers to service the carbs. If they have split, replacement may be the only option and I would expect to have to pay for the parts and labour. It is a common problem with older bikes. Less likely but possible is that the rubbers are fine but haven't been properly replaced. I wouldn't expect to have to pay the labour to rectify such a mistake.
posted by BenPens at 3:16 AM on June 17, 2013

I've always found that a can of 'old school' plain and simple Gumout did wonders for the 'old school' carbs and spark plugs. Blast a spray into each running carb once a year; and dump a bottle into the tank a couple of times a year.

http://www.gumout.com/ourProducts/carbChokeCleaner.asp?submenuheader=6

http://www.gumout.com/ourProducts/all-In-OneFSC.asp

Or, spray down the carbs well; and then empty the rest of the can right into the tank. Yeah, vapors are going to be strong; but not explosive.
And I don't even know if this 50+ year old product is even legal in Cali now...

Yeah, yur shop needs to fix your bike; tooo easy of a job to miss mark on.
posted by buzzman at 5:46 AM on June 17, 2013

under_petticoat_rule: "Also, you didn't ask, but you can learn to clean your carbs yourself... Also neoprene gloves"

Those would be really hard to work in; I think you meant nitrile.

Don't ride your bike until your mechanic has sorted it out. I agree with someone above who says it sounds like it's running lean but that could have a number of causes (the fuel flow could be obstructed or the airbox might be unseated from the carburetors.) Lean engines run very hot and it's possible to burn a hole in a piston or do other real and very expensive damage. Don't ride it when you know it's running wrong.

Your mechanic is on the hook for fixing your bike and I'm seriously unimpressed that he returned it to you in this condition. Also, $650 seems like a lot of money to clean carburetors. I see you're in South Pasadena; when you've gotten your current mechanic to resolve this situation I suggest you ask the Adventure Rider California subforum for suggestions to find a better wrench.
posted by workerant at 9:04 AM on June 17, 2013

Response by poster: I was a little paranoid that the issue was something dumb, like an empty tank, so last night I filled it up to test it out again. I have a two gallon tank, and I put 1 gallon in to fill it, so it had some gas in there.

I ran it a little after putting the gas in, and it seemed to be better, but I wasn't sure and I didn't want to ride it far in the dark, so I didn't test much.

Today I tested again and here is what happened:

I started it, without issue, with the choke all the way out. RPM immediately went to 4k. (In the past, it has taken a while to move up to around 3.5k RPM.) I adjusted the idle so that it went down to 3.5.

I sat there and waited a minute or two and then quickly pushed the choke all the way in. (In the past, doing this would result in an immediate drop in RPM.) There was no immediate response, though it went down to 1.5 after that. I watched it idle at 1.5 and then randomly surge up to 2k RPM about every one and a half seconds, and then fall back down to 1.5k RPM.

I watched it idle for another minute as the RPM slowly moved down, continuing to surge up about .5k RPM every couple seconds. When the RPM was low, turning the throttle had a delayed response, feeling almost like it was out of gas, until the RPM went up. Felt pretty normal as long as the RPM was higher. Letting it idle, it eventually got below .5 and the engine died.

It wouldn't start again until I pulled the choke back out. When I pulled the choke out, it did start, but as I watched, the RPM decreased over the next 25 seconds until the engine died again.

Thoughts?
posted by brenton at 8:48 PM on June 18, 2013