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Discussion Starter #1
Hi all. Took the front sprocket out and the wheel off to clean and lube. As well as the chain. I put it all back together and lubes it all up. Still had it up on te stand and put it in gear to see If all was workig good. On the front sprocket covet I could see the cable and housing moving in and out as the sprocket turned. I undid it and tightened it again. I made sure it was tight and sitting flush on the bold and nothing wedged behind it. Now I'm getting a bit of vibration and noise when riding. Any ideas guys? Also the bike is missing hold holding constant speed. While accelerating it's doesn't miss. Only when holding speed. I don't know if I've done something wrong.
 

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Just an idea, but did you put the sprocket on the wrong way; ie back to front. This might cause an issue with the spline location.

Or you have bent the shaft tightening it up to 1,000,000 nm of torque.

Best to take a few pictures and post them up. With the spocket off as well.
 

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ASTAR said:
Just an idea, but did you put the sprocket on the wrong way; ie back to front. This might cause an issue with the spline location.

Or you have bent the shaft tightening it up to 1,000,000 nm of torque.

Best to take a few pictures and post them up. With the spocket off as well.
Or trying to get the fucker off.

Describe "missing holding" better, so far it sounds unrelated but another problem.
 

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Discussion Starter #5
I made sure it went on the same way I took it off. It has like a spacer on the side that goes on the back and the front is flat. Dont think I bent anything. I was very careful when loosening and tightening everything. It was my first time so I went slow and took my Time[hr]
dayeve said:
ASTAR said:
Just an idea, but did you put the sprocket on the wrong way; ie back to front. This might cause an issue with the spline location.

Or you have bent the shaft tightening it up to 1,000,000 nm of torque.

Best to take a few pictures and post them up. With the spocket off as well.
Or trying to get the fucker off.

Describe "missing holding" better, so far it sounds unrelated but another problem.
it tends to skip a beat. It cuts fuel for a spilt second like it's backfiring but no sound. I think that might be feul related though. I forgot to fill up the other day and it ran out of petrol. Might be some gunk gone through the carbs.
 

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If you're sure that the sprocket is fitted correctly, I feel that the vibration is because the speedo gear is not lined up correctly.

Either that or the chain is too loose, dirty and not lubed sufficiently.
 

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It's been a while since Ive done a CBR Spocket. Does the Speedo drive keyway into the output shaft? If so - you wouldn't be able to bolt it down flat onto the sprocket cover if it wasn't lined up or fitted correctly.

Have you pulled the sprocket cover off and ran the bike on a rear stand in gear to see if the front sprocket is running true and not wobbling?

And does the speedo needle bounce around at low speed?
 

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Discussion Starter #9
ASTAR said:
It's been a while since Ive done a CBR Spocket. Does the Speedo drive keyway into the output shaft? If so - you wouldn't be able to bolt it down flat onto the sprocket cover if it wasn't lined up or fitted correctly.

Have you pulled the sprocket cover off and ran the bike on a rear stand in gear to see if the front sprocket is running true and not wobbling?

And does the speedo needle bounce around at low speed?
Yeh that's right it does. It won't sit flush on the cover unless it's alined. I tried running it with no cover on but u can't really see the wobble in it. It's when the cover is on that you can see the cover wobbling. The speedo is fine and consistant. No bouncing at low or high speed.[hr]
I checked the chain. It's got 2.5cm slack. It's standard between 2 and 2.5, I think? Should I maybe tighten the chain a bit? Would a loose chain cause the sprocket to not spin properly though?
 

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Do you have the metal plate in between the Cover and the engine. I'll see if I can find a diagram of it.

If this isn't put back then the cover will be on an angle resulting in miss alaignment between the speed pickup and output shaft

Edit: Just found it. Have a look at my attachment. Its circled in red!
 

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Discussion Starter #11
ASTAR said:
Do you have the metal plate in between the Cover and the engine. I'll see if I can find a diagram of it.

If this isn't put back then the cover will be on an angle resulting in miss alaignment between the speed pickup and output shaft

Edit: Just found it. Have a look at my attachment. Its circled in red!
Yeh I cleaned it and put it back in place. Goes between the top two bolts and only fits one way
 

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robbie said:
ASTAR said:
Do you have the metal plate in between the Cover and the engine. I'll see if I can find a diagram of it.

If this isn't put back then the cover will be on an angle resulting in miss alaignment between the speed pickup and output shaft

Edit: Just found it. Have a look at my attachment. Its circled in red!
What about it? It's a piece of metal that sits behind the sprocket cover. I put it back on as well. I think it acts like a spacer to keep the sprocket cover even.
Ok, so you have that in place.

Not sure then, maybe try my suggestion of riding without the speedo drive to see if the vibration goes away. It will eliminate some doubts to what it is.

Good Luck.
 

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Discussion Starter #13
ASTAR said:
robbie said:
ASTAR said:
Do you have the metal plate in between the Cover and the engine. I'll see if I can find a diagram of it.

If this isn't put back then the cover will be on an angle resulting in miss alaignment between the speed pickup and output shaft

Edit: Just found it. Have a look at my attachment. Its circled in red!
What about it? It's a piece of metal that sits behind the sprocket cover. I put it back on as well. I think it acts like a spacer to keep the sprocket cover even.
Ok, so you have that in place.

Not sure then, maybe try my suggestion of riding without the speedo drive to see if the vibration goes away. It will eliminate some doubts to what it is.

Good Luck.
true. I'll try it in the morning. Thanks for all the advice though
 

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Discussion Starter #14
Hi all.

Just an update, I took the sprocket cover off and ran the bike on the stand. The front sprocket and the bolt arent spinning properly. So I assume it has nothing to do with the speedo cable alingment. Took the sprocket off and checked it was clean and no gunk stuck behind it and put it back on. Same problem, still wobbling. I have no idea what I've done wrong??

Can someone please confirm that with the front sprocket, the side with the writing goes inwards?facing the engine. I'm pretty sure that's how it was when I first took it off.

Also is this a good excuse to get a chain and sprocket upgrade? Should it I
fix the problem? If it would fix it then I could maybe kill two birds with one stone.....
 

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look at your sprocket, the teeth will most likely have one face which is relatively flat and one with a curve in it. the face with the curve should point towards the front of the bike on the teeth that are pointing up, and towards the rear on the teeth that are pointing down. don't worry about the writing.
 

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Discussion Starter #16
banana.logic said:
look at your sprocket, the teeth will most likely have one face which is relatively flat and one with a curve in it. the face with the curve should point towards the front of the bike on the teeth that are pointing up, and towards the rear on the teeth that are pointing down. don't worry about the writing.
I'm sorry I didn't get what you mean. So the side with the curves in the teeth faces outwards, so it's the side that you can see when it's in the bike? And the flat side sits inwards on the block? Also what do you mean by teeth pointing up and teeth pointing down?
 

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Discussion Starter #18
banana.logic said:
sorry, does your sprocket look at all like this


that pic has it facing the right way
Sorry mate not sure what I supposed to be looking for. I'll take similar pics of mine ad post them up on 10 minutes. Mine seems to be curved inwards on both sides.[hr]
heres the pics of my sprocket
 

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Discussion Starter #19
could this be right?

http://faq.ninja250.org/wiki/My_front_sprocket_%22wobbles%22

if so then what is causing the vibrations on the bike? also when i took it for a ride yesterday it almost came out from under me everytime i hit the throttle a bit or put a slight lean on it around corners or if i hit a bump or groove in the road. and it was hard to steer. the bike was wobbling all over the place was i couldnt go over 40km/hr. it felt like i have a flat tyre but both tyres have good air in them.

i just assumed it was the front sprocket from the wobble that was on it but apparently according to this the wobble in it is normal and its designed that way...

could it be alignment of the rear sprocket and chain?
Or maybe the rear tyre? (i noticed that there was a little sticky thing on the inside of the rim from when they balence the tyre but the little weight wasnt there. maybe it came off and im getting play in the rear wheel?)

im pulling all my hair out trying to figure this out. any feedback guys and gals?
 
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