Full backstory, may not all be relevant but I'll include it in case - I have a 99 SV650 (carburated) track bike that's been in storage for a while. Float bowls were drained, bike was put on a trickle charger, gas tank full of Shell 91 with Seafoam in to stabilize it. Kept (mostly) in a heated garage.
Pulled it out this year, put it on a charger for a bit, bike would crank but wouldn't turn over. Used a trickle charger / maintainer, but when the battery started to run down, switched to an automotive style charger, and used the 75 A starter setting to turn the bike over when the battery was completely dead. (as I'm thinking about it now, I'm wondering if this might have damaged my battery). Went with Quick Start, still wouldn't catch. Drained the fuel, replaced with fresh and included Seafoam in anticipation of some gunk in the carbs.
Discovered the petcock was stuck closed, was able to unstick it. Fuel filter looks clean, petcock full of gunk, cleaned it out, but tank didn't seem to be full of crud. Diaphragms weren't torn, went back together, bike starts and idles. Doesn't sound great, but figured the Seafoam (which I've had success with previously) needed some time to work it's magic.
Since it's a track only bike, I rode it around the block a couple of times, but couldn't really do a full shakedown.
Get to the track yesterday, and it runs like crap. For my first session, it starts and idles ok, but as soon as I get on the gas it starts sounding and feeling like it's running on only one cylinder. At WOT, it is slow to respond (making downshifting difficult), on straightaways it bucks and apparently backfires...it's not fun. I'm thinking at this point it's a carburation issue - one cylinder is working fine, but not the other. This tells me it's not a fuel problem - if it was a fuel problem it would affect both cylinders equally, which would make the bike hard to start and idle.
Throughout the day, the bike gets harder and harder to start, and in my last 2 sessions I need a bump start - the starter motor won't even turn over. It's clear that either the battery is dead and / or there's a problem with the charging system.
This bike is a former race bike, and was heavily modified. The wiring harness is cut right down, so there's no superflous electrical remaining - there's no gauges at all, for example. So the load on the battery while it's running isn't a huge one.
I don't know if I have two problems (carburator issue and dead batter) or one (some sort of larger electrical issue - stator / rotor / coil).
Next steps - put the batter on a charger and see what kind of charge it holds and pull the spark plugs to check their condition and to check for spark. Afterh that I may pull the carbs and check the float bowls. Maybe I have a dislodged jet - since it idles fine and only craps out under throttle, perhaps a main jet has come loose. Would be weird, but I know it's happened before.
Any and all thought welcome. Will update as I make progress. Looking to get all this resolved by next Friday, I have a track session booked at GB and it'd suck if I couldn't make it. Just put some new suspenders on the bike and man is it magical in the corners.
Peace and grease.
O
Pulled it out this year, put it on a charger for a bit, bike would crank but wouldn't turn over. Used a trickle charger / maintainer, but when the battery started to run down, switched to an automotive style charger, and used the 75 A starter setting to turn the bike over when the battery was completely dead. (as I'm thinking about it now, I'm wondering if this might have damaged my battery). Went with Quick Start, still wouldn't catch. Drained the fuel, replaced with fresh and included Seafoam in anticipation of some gunk in the carbs.
Discovered the petcock was stuck closed, was able to unstick it. Fuel filter looks clean, petcock full of gunk, cleaned it out, but tank didn't seem to be full of crud. Diaphragms weren't torn, went back together, bike starts and idles. Doesn't sound great, but figured the Seafoam (which I've had success with previously) needed some time to work it's magic.
Since it's a track only bike, I rode it around the block a couple of times, but couldn't really do a full shakedown.
Get to the track yesterday, and it runs like crap. For my first session, it starts and idles ok, but as soon as I get on the gas it starts sounding and feeling like it's running on only one cylinder. At WOT, it is slow to respond (making downshifting difficult), on straightaways it bucks and apparently backfires...it's not fun. I'm thinking at this point it's a carburation issue - one cylinder is working fine, but not the other. This tells me it's not a fuel problem - if it was a fuel problem it would affect both cylinders equally, which would make the bike hard to start and idle.
Throughout the day, the bike gets harder and harder to start, and in my last 2 sessions I need a bump start - the starter motor won't even turn over. It's clear that either the battery is dead and / or there's a problem with the charging system.
This bike is a former race bike, and was heavily modified. The wiring harness is cut right down, so there's no superflous electrical remaining - there's no gauges at all, for example. So the load on the battery while it's running isn't a huge one.
I don't know if I have two problems (carburator issue and dead batter) or one (some sort of larger electrical issue - stator / rotor / coil).
Next steps - put the batter on a charger and see what kind of charge it holds and pull the spark plugs to check their condition and to check for spark. Afterh that I may pull the carbs and check the float bowls. Maybe I have a dislodged jet - since it idles fine and only craps out under throttle, perhaps a main jet has come loose. Would be weird, but I know it's happened before.
Any and all thought welcome. Will update as I make progress. Looking to get all this resolved by next Friday, I have a track session booked at GB and it'd suck if I couldn't make it. Just put some new suspenders on the bike and man is it magical in the corners.
Peace and grease.
O
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