(PART 1)
Hi,
Second post here, and the reason I signed up!
I have been troubleshooting a problem with my k2 750 over the last week or two that nearly would have cost me a small fortune, as I feared it was gearbox rebuild time which can cost hundreds.
I believe this to be a valid troubleshooting suggestion for the symptoms below for ALL GSXRs from SRADs onwards. Please correct me if you know otherwise.
Thanks in no small part to this forum, I found literally a couple of threads (out of hundreds of search results) that pointed me to the fix. Without this forum, I'd probably be paying someone a lot of money to try to diagnose this problem for me, and I bet the actual issue would get overlooked and it'd get put down to the gearbox needing a rebuild/worn dogs/anything transmission related.
DISCLAIMER...
First of all, I'm no mechanic. I'm happy doing basic maintenance and currently look after my GSXR, my car, and a little Aprilia 2stroke race rep. Just basics, oil & filter, air filter, plugs, the stuff that all bike owners really should be doing themselves... But yeah I'm not a mechanic so feel free to correct me if I label something incorrectly, or I do something in the wrong way. ALSO I'm not responsible if you have a similar problem to what I'm about to describe, and this fix does not help, or you follow what I say and break something on your bike.
This worked for me, and I hope I can help someone else, save them the time and effort I've been through in the last couple of weeks trying to troubleshoot this!
THE PROBLEM...
Ok so in any gear, at any speed, at the redline or just coasting, sometimes my bike would find a false neutral. Then refuse to find a gear, sometimes leaving me by the side of the road wondering how the lady luck I was going to get home.
Then once I'd blagged a gear and limped home, it'd be acting like it was in gear... not starting unless the kickstand was up, so I'd get it started, then slowly let the clutch out and guess what? It isn't in gear.
Over the next week or so I went through every (semi) logical step I could think of to find the problem, including:
Kickstand switch (logic being if it was faulty, it would have at least cut the drive/spark - I cleaned, and oiled the spring and switch)
Gear position sensor (removed, cleaned, replaced)
Gear lever linkage (removed, cleaned, greased, replaced)
Possible killswitch fault (again logic being if faulty, it could retard the spark/cut drive)
I know that strictly speaking, none of the above would have the power to create a false neutral, though I was at the end of my logical thought process trying to figure out what was happening to my gorgeous superbike (remember when 750s were considered superbikes? Well mine still is
).
GEARBOX FAILURE?
No. It can't be. Never in the thousands of miles I've had this bike for has it jumped out of gear. Be it 2nd, 3rd or any of them. My first big bike was a YZF600R which had gearbox troubles, I'm well aware of what an unwell gearbox feels like to ride and the GSXR has never felt that sloppy/unreliable.
I very rarely shift clutchlessly - I don't really see the point on the road, the clutch is there for a reason in my opinion.
I don't do many clutched up wheelies, not any other form of continued gearbox abuse. SO, while at the back of my mind I'm looking for any other possible explanation for my gearbox weirdness, I fully was expecting there to be some quirk meaning I might have to pay someone a lot of money to rebuild my transmission.
THE REAL CAUSE...
This gearbox weirdness is caused by a loose bolt. Not just any bolt though, the bolt which secures the gearchange cam in place. This is found behind the clutch and primary drive.
Instructions and pics follow to access and fix:
THE FIX...
You will need:
A clutch cover gasket unless you KNOW yours is reusable
A brick or small length of 2x4
5mm allen key (hex key for my American brothers?) or drill bit
Socket set with 30mm socket
Small blunt flathead screwdriver
Torque wrench if you're by the book
Breaker bar
Various other tools that I've probably forgotten
Always put bits you remove, be they bolts or clutch baskets, somewhere clean and safe.
Start by wheeling your back tyre over and on to the brick/2x4 then lean the bike over onto it's side stand. Chock the front wheel with offcuts/bricks or anything heavy and suitable. For extra security leave your steering lock on too. This angle will leave the bike completely safe on it's side stand and yet mean you can open the clutch cover and LOSE NO ENGINE OIL. Make sure your bike is cold, doesn't have to be stone cold but if you've just ridden it at least give the oil a chance to drain back down through the lump.
Also at this point remember to leave your bike in gear, any one will do - I couldn't tell which gear mine was in, just as long as it's in gear that's all good.
Next, whip the clutch cover off, there's a few bolts holding it in place. 2 will have cable holders in place, remember where they went. You should now be looking at 5 clutch springs, it'll look something like this:
imagehosting
Remove the clutch springs using a socket set/ratchet. Ideally take them off a bit at a time, so you're keeping the load as even as possible. Not essential, just good practice
I used the clutch cover itself as a tray for all bolts, springs and washers I removed as they were all covered in oil. Once the springs are out, you'll be looking at this:
take a screenshot
You can now remove the clutch holder (spring holder? plate holder? whatever, the central silver bit you just removed the springs from) and you'll see this:
picture upload
You can now remove the clutch lifter and bearing and washer from the middle of the spindle, in the center of the clutch basket. It will just lift out. Obviously be very careful with all of these internal components, again I put this in the nice oily safety of the inside of the clutch cover I'd already removed.
At this point you can start to remove the clutch plates, one by one. Though probably not essential, it's certainly advisable to put them back EXACTLY as they came out, so (tool time top tip coming up) take them off one by one and place them on the footrest as pictured. Straight out of the clutch basket, one at a time, and straight on the footrest. So you'll end up with a stack that just needs to go back in, one by one and it'll be perfect.
I learned that you can feel around the edge/back of the clutch basket and pull the whole stack forwards to get the last half of the plates out much more easily. I still needed to use a blunt, flat screwdriver to help hold one edge in place while I coaxed the other side out. WARNING - sharp, precision-engineered bits are present here that are designed to make your knuckles bleed. Go slow and take your time, do not force anything.
Once all plates are out (and hanging on your footrest) you'll see this:
uploading pictures
Deep in the clutch basket you'll see a big-mumma nut, 30mm, reach for the breaker bar. WAIT! Undoing this nut WILL make your wheel spin, it'll kick out the brick or 2x4, your bike will fall on to you and you'll impale yourself anally on to a bmx stunt peg and face an embarrassing and painful trip to the hospital.
The reason you left it in gear, is because you (like me) don't have a clutch holder, and you realised that to undo this nut you'd need the bike in gear right?
Well, you'll need to position yourself so you can put a DECENT amount of force onto your back brake lever (consider moving that bmx out of the way too) to lock the wheel > sprockets > crank in place to you can undo that nut. BY THE WAY... this nut is staked, meaning you can unstake it before doing this, or just do what I did and unstake it by undoing it. You should ALWAYS re-stake this nut, or if it's obviously been done many times, replace it.
With the back brake FIRMLY on, that nut will come loose easily. I used an 18" breaker and it was no trouble at all.
Mini disclaimer - no stunt pegs were hurt during this stage of the process.
The nut and it's washers should look like this:
upload photo
Mine had a thick washer, then a thinner one. As with all of this stuff, remember where it went, in what order, take pics or label things. It's easy to get wrong, especially the first time you attempt something like this. I used a bit of old cardboard to lay the bigger bits out on in the order they were removed in, around here we call this an "idiot board":
how to do a screen shot
Anyway, with that nut out of the way, you'll be able to slide out the inner part of the clutch basket:
image posting
Hi,
Second post here, and the reason I signed up!
I have been troubleshooting a problem with my k2 750 over the last week or two that nearly would have cost me a small fortune, as I feared it was gearbox rebuild time which can cost hundreds.
I believe this to be a valid troubleshooting suggestion for the symptoms below for ALL GSXRs from SRADs onwards. Please correct me if you know otherwise.
Thanks in no small part to this forum, I found literally a couple of threads (out of hundreds of search results) that pointed me to the fix. Without this forum, I'd probably be paying someone a lot of money to try to diagnose this problem for me, and I bet the actual issue would get overlooked and it'd get put down to the gearbox needing a rebuild/worn dogs/anything transmission related.
DISCLAIMER...
First of all, I'm no mechanic. I'm happy doing basic maintenance and currently look after my GSXR, my car, and a little Aprilia 2stroke race rep. Just basics, oil & filter, air filter, plugs, the stuff that all bike owners really should be doing themselves... But yeah I'm not a mechanic so feel free to correct me if I label something incorrectly, or I do something in the wrong way. ALSO I'm not responsible if you have a similar problem to what I'm about to describe, and this fix does not help, or you follow what I say and break something on your bike.
This worked for me, and I hope I can help someone else, save them the time and effort I've been through in the last couple of weeks trying to troubleshoot this!
THE PROBLEM...
Ok so in any gear, at any speed, at the redline or just coasting, sometimes my bike would find a false neutral. Then refuse to find a gear, sometimes leaving me by the side of the road wondering how the lady luck I was going to get home.
Then once I'd blagged a gear and limped home, it'd be acting like it was in gear... not starting unless the kickstand was up, so I'd get it started, then slowly let the clutch out and guess what? It isn't in gear.
Over the next week or so I went through every (semi) logical step I could think of to find the problem, including:
Kickstand switch (logic being if it was faulty, it would have at least cut the drive/spark - I cleaned, and oiled the spring and switch)
Gear position sensor (removed, cleaned, replaced)
Gear lever linkage (removed, cleaned, greased, replaced)
Possible killswitch fault (again logic being if faulty, it could retard the spark/cut drive)
I know that strictly speaking, none of the above would have the power to create a false neutral, though I was at the end of my logical thought process trying to figure out what was happening to my gorgeous superbike (remember when 750s were considered superbikes? Well mine still is
).GEARBOX FAILURE?
No. It can't be. Never in the thousands of miles I've had this bike for has it jumped out of gear. Be it 2nd, 3rd or any of them. My first big bike was a YZF600R which had gearbox troubles, I'm well aware of what an unwell gearbox feels like to ride and the GSXR has never felt that sloppy/unreliable.
I very rarely shift clutchlessly - I don't really see the point on the road, the clutch is there for a reason in my opinion.
I don't do many clutched up wheelies, not any other form of continued gearbox abuse. SO, while at the back of my mind I'm looking for any other possible explanation for my gearbox weirdness, I fully was expecting there to be some quirk meaning I might have to pay someone a lot of money to rebuild my transmission.
THE REAL CAUSE...
This gearbox weirdness is caused by a loose bolt. Not just any bolt though, the bolt which secures the gearchange cam in place. This is found behind the clutch and primary drive.
Instructions and pics follow to access and fix:
THE FIX...
You will need:
A clutch cover gasket unless you KNOW yours is reusable
A brick or small length of 2x4
5mm allen key (hex key for my American brothers?) or drill bit
Socket set with 30mm socket
Small blunt flathead screwdriver
Torque wrench if you're by the book
Breaker bar
Various other tools that I've probably forgotten
Always put bits you remove, be they bolts or clutch baskets, somewhere clean and safe.
Start by wheeling your back tyre over and on to the brick/2x4 then lean the bike over onto it's side stand. Chock the front wheel with offcuts/bricks or anything heavy and suitable. For extra security leave your steering lock on too. This angle will leave the bike completely safe on it's side stand and yet mean you can open the clutch cover and LOSE NO ENGINE OIL. Make sure your bike is cold, doesn't have to be stone cold but if you've just ridden it at least give the oil a chance to drain back down through the lump.
Also at this point remember to leave your bike in gear, any one will do - I couldn't tell which gear mine was in, just as long as it's in gear that's all good.
Next, whip the clutch cover off, there's a few bolts holding it in place. 2 will have cable holders in place, remember where they went. You should now be looking at 5 clutch springs, it'll look something like this:
imagehosting
Remove the clutch springs using a socket set/ratchet. Ideally take them off a bit at a time, so you're keeping the load as even as possible. Not essential, just good practice
I used the clutch cover itself as a tray for all bolts, springs and washers I removed as they were all covered in oil. Once the springs are out, you'll be looking at this:
take a screenshot
You can now remove the clutch holder (spring holder? plate holder? whatever, the central silver bit you just removed the springs from) and you'll see this:
picture upload
You can now remove the clutch lifter and bearing and washer from the middle of the spindle, in the center of the clutch basket. It will just lift out. Obviously be very careful with all of these internal components, again I put this in the nice oily safety of the inside of the clutch cover I'd already removed.
At this point you can start to remove the clutch plates, one by one. Though probably not essential, it's certainly advisable to put them back EXACTLY as they came out, so (tool time top tip coming up) take them off one by one and place them on the footrest as pictured. Straight out of the clutch basket, one at a time, and straight on the footrest. So you'll end up with a stack that just needs to go back in, one by one and it'll be perfect.
I learned that you can feel around the edge/back of the clutch basket and pull the whole stack forwards to get the last half of the plates out much more easily. I still needed to use a blunt, flat screwdriver to help hold one edge in place while I coaxed the other side out. WARNING - sharp, precision-engineered bits are present here that are designed to make your knuckles bleed. Go slow and take your time, do not force anything.
Once all plates are out (and hanging on your footrest) you'll see this:
uploading pictures
Deep in the clutch basket you'll see a big-mumma nut, 30mm, reach for the breaker bar. WAIT! Undoing this nut WILL make your wheel spin, it'll kick out the brick or 2x4, your bike will fall on to you and you'll impale yourself anally on to a bmx stunt peg and face an embarrassing and painful trip to the hospital.
The reason you left it in gear, is because you (like me) don't have a clutch holder, and you realised that to undo this nut you'd need the bike in gear right?
Well, you'll need to position yourself so you can put a DECENT amount of force onto your back brake lever (consider moving that bmx out of the way too) to lock the wheel > sprockets > crank in place to you can undo that nut. BY THE WAY... this nut is staked, meaning you can unstake it before doing this, or just do what I did and unstake it by undoing it. You should ALWAYS re-stake this nut, or if it's obviously been done many times, replace it.
With the back brake FIRMLY on, that nut will come loose easily. I used an 18" breaker and it was no trouble at all.
Mini disclaimer - no stunt pegs were hurt during this stage of the process.
The nut and it's washers should look like this:
upload photo
Mine had a thick washer, then a thinner one. As with all of this stuff, remember where it went, in what order, take pics or label things. It's easy to get wrong, especially the first time you attempt something like this. I used a bit of old cardboard to lay the bigger bits out on in the order they were removed in, around here we call this an "idiot board":
how to do a screen shot
Anyway, with that nut out of the way, you'll be able to slide out the inner part of the clutch basket:
image posting
