Bought a bike, broke it right away.

[Taytayflan]

To get it out of the way immediately, I can't take it back, private party sale.

Bought a 1993 Suzuki GS500 (first bike, new rider). 83XX miles on the odometer, carb rebuild and fuel lines replaced spring 2015. Sounded fine in the parking lot, rode it 4 blocks to a friend's, then 4 hours later after a cold start rode it for ~40 minutes in city and then eventually interstate traffic when the problem occured.

At highway speed (dunno exact speed, comfortably in 5th gear, more worried about keeping pace with traffic, so 55-70mph), a vehicle speeds up on an on ramp to my side. I had a car to my left, a car behind, and didn't believe the joining vehicle saw me, so I downshifted 2, possibly 3 gears (into 3rd or 2nd) and opened the throttle up to get ahead. I believe I did for a moment, and then started losing power while a loud clicking noise developed. I eventually didn't have enough power to keep going, leaving me stranded on the road. The power decrease seemed pretty linear after I noticed it. Toying with the throttle cable while moving gave me a spurt of more power, but I don't know if that is related or just coincidence.

I don't know exactly how many gears I dropped as it was kind of frantic on my part. The last time I shifted I think I forgot to clutch, which looking back shook the bike a fair bit.

I'm lost. Carburetors are new to me, as are motorcycles. The clicking was loud when I was still moving. After I had the bike stopped but still running, I could not apply any throttle or it would lug and try to die. If I put the choke... in? (toggled it some) the bike could rev up to about 4k revs, but sounded like hell with the clicking/knocking sound. The sound is related to engine speed. I cannot start it cold, when I originally had the incident, and gave it throttle enough for it to die, I was able to restart it when it was warm.

Video link one: https://www.youtube.com/watch?v=1oEIXrvIocQ

Video link two: https://www.youtube.com/watch?v=ntzmdhKR0DY

I have compression, according to the local Suzuki shop. I have both sparks (put in new plugs for hell of it), and it certainly smells like I have fuel delivery. I have a feeling, but no real evidence, that the previous owner never revved it into the high part of the bike's rev range, which I certainly did in the incident. Also, they believed the "Prime" position on the fuel switch thingy was the "On" position.

Any help or directions or ideas to start chasing down would be appreciated. I didn't really plan on buying a project bike, but here I go.

(This was posted to a few subreddits, not including their conclusions in the initial post to not bias peoples ideas)

[mr72]

I am going to be the first to tell you, and I am quite sorry to have to tell you, but I think you definitely broke the motor.

I mean hard parts that are expensive to replace.

You may have a bent or broken rod, cracked piston, totally lost a rod bearing, who knows. Something quite bad. The clicking/knocking (if it would run) you hear is the indicator that something bad is broken. Could be the rod wobbling on the crank sans bearing or a connecting rod clanking off of the cylinder wall because it's broken and flopping around, or the piston hitting a valve, or the broken piston clanking against the cylinder (but this would result in no compression) or a hundred other things, all of them really bad.

And to be quite honest, don't try to blame this on the PO. You probably over-revved this engine by a lot by shifting down from 5th to probably 1st at 70mph. In theory, it should just be a hair over redline at 70mph in 2nd, which is why I think you may have wound up in 1st. Or you were going 80, and shifted to 2nd. etc.

With any luck that would have just fried the clutch but if you did it with no clutch then it's possible you may have chipped a gear and also broken something expensive and hard to get to.

This is not a carburetor problem.

Now, the good news: the GS500 is very easy to work on and parts are cheap, and abundant. Easiest would be to swap the engine, and in the FS section of this forum there are a number available. Rebuilding it yourself is always an option but maybe not a great one if you are not very mechanical. It's an order of magnitude easier to work on than a modern car engine, but it's still something where you have to have parts machined and be very meticulous and that kind of thing. Full disclosure, I have not worked on the GS500 engine but I have rebuilt a modern car engine and I can read about others' experiences with GS500. Along the continuum between a lawn mower on one end and the Miata I worked on on the other, it's way closer to the lawn mower. But most people throw away lawn mowers when they break and never rebuild them, even though it's pretty easy.

[qcbaker]

I'm gonna say +1 to what mr72 said. Downshifting from 5th to 1st/2nd at near 80 definitely would put an enormous amount of strain on the engine and gearbox, ESPECIALLY if you shifted without the clutch at such high RPMs. This can lead to multitude of problems. Loud clicking noise is usually indicative of a serious mechanical failure of some internal engine part (valves, rods, pistons, etc).

If I were you, I would look into replacing the engine.

[mr72]

BTW I'd have to say the engine swap is probably a DIY affair if you can find one from a 1st gen pre-2001 GS500, but fitting a later engine may be more troublesome since some things changed that make it not quite plug and play.

Or, you could always just suck it up and sell the bike as-is, take a loss. Either you swap the motor and maybe put $500 into it (money you'll never, ever get back) and with luck get it running and working, or you might be able to take a $500 loss selling it as-is.

FWIW here in Austin there's a good donor GS500 that has bodywork problems and doesn't presently run but has a good motor for $500. Fairly common, if you're patient. Plus you'd also have a more or less complete parts bike.

[user11235813]

Wow! you are one lucky dude, I think you've got away pretty lightly given the circumstances, someone is looking after you.

[HPP8140]

Sorry, it happened, unnecessary panic. Try the horn first.

[Watcher]

Could be many things, but it's definitely something broken internally.
If you're lucky the damage is minimal and you may be able to get away with replacing the part(s) and doing some internal engine cleanup.  But honestly, you won't know until you pull the engine and start tearing it down.

Luckily enough, an engine swap is definitely a DIY affair.  You don't even need special tools, the most specialized thing you'll need is a set of snap-ring pliers for the final drive sprocket.
Just take your time keeping track of bolts and electrical so you know what goes where and you'll be fine.
The frame even comes apart on one side.  Just use an automotive jack on the engine to support it while you remove all the mounts, then you can either lower the engine out or lift the frame off the top.
The engine is light enough for one person to carry, with 2 people maneuvering it should be no trouble.


And as a lesson, change gears one at a time.  Typically downshifting to gain speed only needs one gear, maybe two if you are cruising in low RPMs.  These bikes start to make good power around the 7k mark, so if you are cruising near that RPM just twist the wrist.
If you're at 4-5k downshift ONCE.
If you're at 2-3k you can go twice.  But until you learn the bikes gearing and comfortable rev range you should ALWAYS clutch out every shift.
Downing 3 or more gears is definitely not advidable, unless you're clutched in and definitely coming to a stop.

[kapiteinkoek]

That battery could use a charge too.

[Watcher]

Just to give you an image of the frame apart and the engine out.  Not much going on, any mechanically inclined person can pull the engine without even consulting a manual.  You'll want to reference torque specs when going back together, of course.



Mine came apart for head work.  It had burned valves from the PO failing to rejet after intake/exhaust change.  Since it was winter and I was working in a machine shop at the time I figured I clean the valves up myself and do some simple mods to the head while it was apart.

It really is an easy job.  If you can find a donor motorcycle you shouldn't be intimidated by the work ahead.

[Taytayflan]

Thanks for all the replies, guys.

It would have been 5th ->3rd or 2nd, not 1st. I'm sure I didn't do four gears. Coming from my daily BRZ, I got used 6th to 3rd in evasive maneuver scenarios, guess I learned the principles don't cross. I have no problem admitting I murdered the engine, just sucks that I'll likely not get to ride the rest of the season.

The shop said the problem was in the "top end." I'm.. still not sure what a "top end" is, I come from working on an old Impreza RS. Is the top end like a header(s)? I've taken the Impreza down to the short block for the head gaskets and timing belt myself, changed the clutch with a friend, replaced the center diff and modified the suspension on it, so I'm not mechanically inept, and usually enjoy learning as I go. Learned to hate exhaust work.

Any chance I can start to peel the engine apart with it still in the bike? I've concluded when I can to crack into it and see if I'm lucky enough that it's just some bent valves and a cam/timing chain off, and if it's not maybe just swap it and have a parts engine.

[mr72]

By "top end" they mean cylinder head.

You can remove the cam cover with the engine in the bike. You can probably pull the head with the engine in the bike but it'd be easier with it off the bike. And then comes what motorcycle guys call the "jug", that is the cylinders, which come off of the block (odd, I know).

If the valves are bent you would have no compression, since bent valves never close. Also if the valves are bent, you'd have holes in the pistons because that's what hit the valves and caused them to bend, which would also cause no compression.

Who knows maybe you got super lucky and just broke the cam chain tensioner and jumped time.

This will be a lot easier than head gasket swap on your Subaru. Does any Subaru ever not need a head gasket? My daughter had one and that car was just a reliability disaster. I haven't even gotten my GS500 to run consistently yet and it's already more reliable than that Subaru. Anyway, if you can do timing belts and head gasket on a Subaru, then you can do whatever the GS engine needs but bear in mind a lot of what you need to do is understand how it works and look for, measure, evaluate, etc. the condition of everything that might be affected. There's a lot of theory in there, and then knowing when to send something to a machine shop. You won't likely be able to just drop parts in without machine work.

[qcbaker]

...
This will be a lot easier than head gasket swap on your Subaru. Does any Subaru ever not need a head gasket? My daughter had one and that car was just a reliability disaster. I haven't even gotten my GS500 to run consistently yet and it's already more reliable than that Subaru.
...

Subarus are pretty reliable, when driven like a sane person. Most legacy/outback owners report great reliablity. Non-WRX Imprezas are extremely reliable cars. Problem is, people who drive WRX's/STIs tend to drive them much harder than most people, so they often have to replace parts sooner.

Oh, and pre '05 WRX head gaskets were seemingly made of toilet paper.

[mr72]

Oh, and pre '05 WRX head gaskets were seemingly made of toilet paper.

Well this was on a '98 Legacy GT that had never been abused. It's just a horrible design. Guaranteed-to-foul head gasket, due to the way oil and coolant sits in the heads. Really, a flat-4 or flat-6 works awesome in an AIR COOLED engine. Virtually all of the 2.5L Subaru DOHC engines of that vintage have constant head gasket troubles, or so I am told. You just have to be prepared to work on it all the time if you own one. I might have made the effort with that car if the rest of the car was perfect, but it wasn't. So I sold it and replaced it with an even worse car (Audi A4), which I very much wanted to set on fire after owning it less than a year. We gleefully traded it in on my wife's car and then gave my daughter our uber-reliable Honda Pilot as a replacement. Not as much fun as either of the other cars but man does it run forever with zero issues (180K so far, we've owned it since new).

Anyway, back to the topic... sorry for the diversion. Point is, if you can stand working on a Subaru, then you will love the GS500. But the problem the OP has is way worse than just a head gasket.

[gsJack]

You can pull the head with the engine in the frame and that's the way I did it when I had a broken exhaust valve caused by a tight bucket while cranking to start one freezing cold morning.  Pulled the gas tank and air box and took the carbs loose and just hung them over the frame on the throttle cables.  It was a tight fit and had to take the wiring loose and out of the way so head could squeeze thru up and out.

Not sure what your clicking noise is so I'd start by pulling tank and valve cover and checking engine timing and then turn the engine over with a wrench on the right end of the crank and observe valve action, cam chain, etc and go from there.  Valve timing:

[qcbaker]

Oh, and pre '05 WRX head gaskets were seemingly made of toilet paper.

Well this was on a '98 Legacy GT that had never been abused. It's just a horrible design. Guaranteed-to-foul head gasket, due to the way oil and coolant sits in the heads. Really, a flat-4 or flat-6 works awesome in an AIR COOLED engine. Virtually all of the 2.5L Subaru DOHC engines of that vintage have constant head gasket troubles, or so I am told. You just have to be prepared to work on it all the time if you own one. I might have made the effort with that car if the rest of the car was perfect, but it wasn't. So I sold it and replaced it with an even worse car (Audi A4), which I very much wanted to set on fire after owning it less than a year. We gleefully traded it in on my wife's car and then gave my daughter our uber-reliable Honda Pilot as a replacement. Not as much fun as either of the other cars but man does it run forever with zero issues (180K so far, we've owned it since new).

Anyway, back to the topic... sorry for the diversion. Point is, if you can stand working on a Subaru, then you will love the GS500. But the problem the OP has is way worse than just a head gasket.

Oh god, my girlfriend owned a 2000 A4 and it was nothing but trouble. I hated that car with every fiber of my being. Every time I fixed something, something else would break.

But yeah, sorry for the thread drift. +1 to the GS being easy to work on. I'm anything but an experienced mechanic, and I haven't run into anything on my GS that I could take apart but wasn't able to put back together. Haven't had to mess with the engine or carbs much yet, thankfully, but I was able to replace basically my entire front end with minimal issue.

Mr72 is right, if you're comfortable working on your Subaru, you'll for sure be able to at the very least do an engine swap without too much of a problem. Good luck mate.

[Watcher]

It would have been 5th ->3rd or 2nd, not 1st. I'm sure I didn't do four gears. Coming from my daily BRZ, I got used 6th to 3rd in evasive maneuver scenarios, guess I learned the principles don't cross.

Any chance I can start to peel the engine apart with it still in the bike?

Well, in a car when you have a dedicated slot for each gear you can know FOR SURE where you're putting it.
In a sequential gearbox it's down to you to know where you are.  You thought you were in 5th, but could you have been in 4th?
You say you only clicked down 2-3 times, but if you were nervous could you have accidentally clicked down a 4th time?  If you were flustered enough to let out the clutch too early anything is possible.
A lot of people get gear indicators for this very reason.

But for me, I've long since stopped counting and now can more or less go by instinct, but the bottom line is still that I shift one at a time and I prepare myself for issues in traffic well ahead of time.
Like, same scenario as you.  I'm boxed in and see a car approaching to merge.  I'd downshift once and clutch out to bring the revs up in preparation to move, but in the end I may end up shifting back up to cruising speed if nothing goes down.
Also in this case if I REALLY need power I'll know if I can go down again, and I can go down a gear in a fraction of a second, but I was already prepared to gas it and go from being in a lower gear already.

A lot of it boils down to your experience level and knowing what to look for.



As far as pulling the engine to get at the head, as others have said you can do it in the frame.  But honestly, with 4 motor mounts, 4 bolts on the frame, and something like 3 wires to disconnect, having it out of the bike isn't much more work and makes handling the engine a lot easier.  Especially if it turns out not to be just head work, you'll have to end up pulling it anyway to get at the jugs/crankcase or to do a complete swap.
If you've got the room on a bench in the garage, I say just pull it.