What did you do to your bike today?

SPARC said:
So i'm not really sure if these results mean that with a 30psi difference when oil is sealing the rings that 1,2 and 4 need new rings. As for 3 well maybe that's fine ... no idea.

:confused:
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Put it this way, slightly low compression on one cylinder won't be responsible for it topping out at 60mph. It's far, far more likely you have a problem with the carbs or possibly ignition. It's quite possible you just put a bit less oil in that cylinder than the others since the dry readings are identical.
 
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Surely you'd get white/blue smoke and be burning a lot of oil if your rings are going,and at 41k I'd be very surprised
 
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SPARC said:
well yes but that better seal must mean that the rings were bad in the first place ? I don't know. It's a funny old thing this diagnosing engine problems when you don't have a scooby and the haynes doesn't really explain it that well if at all. Cylinder 3 must have other issues besides the rings as it's no where near spec which is 185-191 according to the haynes manual.
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the high psi the manual says is surely when new.
what the service limit before a rebore is needed.

one cylinder down a little , you really wouldn't notice at all riding the bike and it wouldn't make the bike top out at 60.
I had 1 cylinder right down below the service limit and the bike still ran fine and would still do 120 on my private road lol.
3 at 180 and 1 at 165 is nothing to worry about as far as the engine not running right.
do that flush to see if its a stuck ring. but even if it makes no difference
I still wouldn't tare the engine down to try and fix it.
I'd be looking elsewhere for the problem, because compression isn't the problem if the bikes as slow as it is
 
wazza300 said:
Surely you'd get white/blue smoke and be burning a lot of oil if your rings are going,and at 41k I'd be very surprised
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My mate says there is black smoke coming out but only when I am hitting off that 8k rev limit. That's why I originally suspected oil in the cylinders. :(

ShakenNstirred said:
the high psi the manual says is surely when new.
what the service limit before a rebore is needed.

one cylinder down a little , you really wouldn't notice at all riding the bike and it wouldn't make the bike top out at 60.
I had 1 cylinder right down below the service limit and the bike still ran fine and would still do 120 on my private road lol.
3 at 180 and 1 at 165 is nothing to worry about as far as the engine not running right.
do that flush to see if its a stuck ring. but even if it makes no difference
I still wouldn't tare the engine down to try and fix it.
I'd be looking elsewhere for the problem, because compression isn't the problem if the bikes as slow as it is
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That flush is on the cards next week. Got the full week off so flush and see where I'm at. I don't have high expectations for it but it won't hurt to do it. Then from there I'll see if the carbs are coming out. The bike pulls like a train all the way until it hits 8k/60mph whichever is first. I'm determined to fix it :D
 
Could be ht leads or coils aswell,sems strange you have an 8k cut off,carbs might help from a clean

When does the rev limiter kick in? I wonder if they play up?

With worn rings you'd use more oil though and see blue smoke at cold start up and general running
 
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Nothing wrong with your rings you need to be looking some place else.

compression tests are a hit and miss affair at the best of times and yours is not the reason for lack of power.
 
New 'un!

2005, 26hours total use. New clutch and 3 spare, new chain.
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SPARC said:
My mate says there is black smoke coming out but only when I am hitting off that 8k rev limit. That's why I originally suspected oil in the cylinders. :(



That flush is on the cards next week. Got the full week off so flush and see where I'm at. I don't have high expectations for it but it won't hurt to do it. Then from there I'll see if the carbs are coming out. The bike pulls like a train all the way until it hits 8k/60mph whichever is first. I'm determined to fix it :D
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blue smoke oil, black smoke burning to much fuel, white is water being burnt off.

what's it like in the other gears, it going past 8k?
what's it doing at 8k , missing or just doesn't want to rev anymore.
it defintly not the one cylinder being a little down, look elsewhere.
carb , air filter first port of call, because black smoke means its over fueling
 
Super jealous of your motocross tracks in the USA! You guys have so much spare land compared to the UK. Here if you try and set up a track people cry about the noise from a mile away.
 
Finished painting my CBR F3 forks and caliper brackets.

Scotchbrite and isoprpyl alcohol before i started
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First coat of self etch
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First coat of wheel trim black
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Caliper brackets painted and laquered
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Brackets fitted to calipers.
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The finished article
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Closer up
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SPARC said:
My mate says there is black smoke coming out but only when I am hitting off that 8k rev limit. That's why I originally suspected oil in the cylinders. :(

That flush is on the cards next week. Got the full week off so flush and see where I'm at. I don't have high expectations for it but it won't hurt to do it. Then from there I'll see if the carbs are coming out. The bike pulls like a train all the way until it hits 8k/60mph whichever is first. I'm determined to fix it :D
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It's not going to be cylinder compression, or anything to do with pistons, bores etc.... it.... it just isn't :D Especially with carbs- you could be running 50psi in one cylinder and you'd be unlikely to notice, simply because carbs are fabulous at adjusting to cylinder and vacuum conditions. Unless something's terminally wrong, and I doubt it because you're not seeing many secondary indications.

If it's not stuttering and it doesn't get worse in the wet (coils or leads), it's going to be a vacuum or fuel issue. I actually doubt it's a mixture issue because that would tend to just cause rough running as it's extremely unlikely to hit all four carbs equally, unless it's a blocked air filter as mentioned. But it'd have to be a pretty dirty filter! If it feels like it hits an artificial redline at a consistent engine speed, my money is on it being fuel flow- either a kinked line somewhere, a blocked filter or dodgy fuel tap. Is the tank rusty at all inside?
 
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wazza300 said:
Could be ht leads or coils aswell,sems strange you have an 8k cut off,carbs might help from a clean

When does the rev limiter kick in? I wonder if they play up?

With worn rings you'd use more oil though and see blue smoke at cold start up and general running
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.one. said:
Nothing wrong with your rings you need to be looking some place else.

compression tests are a hit and miss affair at the best of times and yours is not the reason for lack of power.
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ShakenNstirred said:
blue smoke oil, black smoke burning to much fuel, white is water being burnt off.

what's it like in the other gears, it going past 8k?
what's it doing at 8k , missing or just doesn't want to rev anymore.
it defintly not the one cylinder being a little down, look elsewhere.
carb , air filter first port of call, because black smoke means its over fueling
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CGrieves said:
It's not going to be cylinder compression, or anything to do with pistons, bores etc.... it.... it just isn't :D Especially with carbs- you could be running 50psi in one cylinder and you'd be unlikely to notice, simply because carbs are fabulous at adjusting to cylinder and vacuum conditions. Unless something's terminally wrong, and I doubt it because you're not seeing many secondary indications.

If it's not stuttering and it doesn't get worse in the wet (coils or leads), it's going to be a vacuum or fuel issue. I actually doubt it's a mixture issue because that would tend to just cause rough running as it's extremely unlikely to hit all four carbs equally, unless it's a blocked air filter as mentioned. But it'd have to be a pretty dirty filter! If it feels like it hits an artificial redline at a consistent engine speed, my money is on it being fuel flow- either a kinked line somewhere, a blocked filter or dodgy fuel tap. Is the tank rusty at all inside?
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Thanks chaps. It hits a rev limit (feels like) at 8k in 1st, 2nd maybe 3rd gear also. After that it's not getting to 8k but 60mph and no further. It does bounce a little 58 - 62 mph. It doesn't scream like on a limit just well farts is the only way I can describe it. Had the fuel **** off the tank as I also suspected maybe a blockage, had a look at the screen inside and it looked brand new. Nothing stuck in it, no specs of dirt or bits of grit/rust in the screen. Tank looked silver inside as far as I could tell looking through the hole.

It doesn't even idle rough, well maybe for the first few minutes as it heats up but after that it's stable at around 1300.
 
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