Discussion
Doing a nice steady 70-80mph on my 954 Fireblade on Sunday, when I suddenly lose power and the engine sounds like the manifold has blown off..
I get it to the side of the road and call the AA who arrive in 20 mins. I'd not long left the A5 near Telford and was on my way back to Bridgenorth.
I get it home, remove the tank and air box to find a sparkplug had been blown out !
The thread in the head is knackered as I could not screw another back in and the electrode is missing from the top, hopefully somewhere in the exhaust or thereafter.
Head needs to come off for repair so it's an engine out job. Something I've never done before, and tbh I'm s
tting myself more and more as the bike comes apart!
Has anyone had this happen? And any tips on removing an engine are more than welcome ...
I get it to the side of the road and call the AA who arrive in 20 mins. I'd not long left the A5 near Telford and was on my way back to Bridgenorth.
I get it home, remove the tank and air box to find a sparkplug had been blown out !
The thread in the head is knackered as I could not screw another back in and the electrode is missing from the top, hopefully somewhere in the exhaust or thereafter.
Head needs to come off for repair so it's an engine out job. Something I've never done before, and tbh I'm s
tting myself more and more as the bike comes apart! Has anyone had this happen? And any tips on removing an engine are more than welcome ...
Why does the engine need to come out? Sounds like there's been a helicoil in place which has failed, or perhaps a stripped thread which was just holding on.
If it was mine, I would helicoil a new thread in, and use a boroscope to look for any parts of the spark plug within the cylinder and remove it.
That should sort you out.
If it was mine, I would helicoil a new thread in, and use a boroscope to look for any parts of the spark plug within the cylinder and remove it.
That should sort you out.
bluezedd said:
Why does the engine need to come out? Sounds like there's been a helicoil in place which has failed, or perhaps a stripped thread which was just holding on.
If it was mine, I would helicoil a new thread in, and use a boroscope to look for any parts of the spark plug within the cylinder and remove it.
That should sort you out.
You must be a betting man!! If it was mine, I would helicoil a new thread in, and use a boroscope to look for any parts of the spark plug within the cylinder and remove it.
That should sort you out.
I’d prob do the same but I wouldn’t say it out loud
Happened to me on a mid 90's CBR600. Took the engine out and head off - quite therapeutic and just cost me a helicoil and a head gasket.
As mentioned just be organised pulling it apart. Current fashion is take photos on your mobile but I'm with Edd China chucking stuff in freezer bags and writing on it with a marker pen what the fixings are for.
I number the bags as well on a bike I've never worked on before as well so you get the sequence right. So No.1 bag says "Front Fairing Bolts" and bag 47 says "Gudgeon Pins". This means when you're rebuilding it (2 years later) you just work backwards through the numbers.
On commercial stuff they get the piston to bottom of the stroke, pump grease into the combustion chamber and do it insitu and then hoover out the metal fillings. Anything left will disappear when you start it up - bit of an animalistic approach.
Cannot really do it on bike heads. There's no proper access and it's nice to make sure the ends of the helicoil are tucked out the way.
As mentioned just be organised pulling it apart. Current fashion is take photos on your mobile but I'm with Edd China chucking stuff in freezer bags and writing on it with a marker pen what the fixings are for.
I number the bags as well on a bike I've never worked on before as well so you get the sequence right. So No.1 bag says "Front Fairing Bolts" and bag 47 says "Gudgeon Pins". This means when you're rebuilding it (2 years later) you just work backwards through the numbers.
On commercial stuff they get the piston to bottom of the stroke, pump grease into the combustion chamber and do it insitu and then hoover out the metal fillings. Anything left will disappear when you start it up - bit of an animalistic approach.
Cannot really do it on bike heads. There's no proper access and it's nice to make sure the ends of the helicoil are tucked out the way.
This is familiar, I think the threads weren't that great on those bikes. I bought my 929 brand new and I was the only one who removed and refitted the plugs and I know I didn't cross thread them. One of mine blew out at 70mph in 2nd taking the thread with it.
I took the engine out, removed the head and got a machine shop to fit a solid thread insert rather than a helicoil because the last thing I wanted was bits of helicoil in the engine without me knowing it when I changed a plug in the future.
Taking the engine out looks bad but it's just a long process that is pretty straightforward. However, one thing to watch is that you need to label the connection to the fuel level sender as it's the same one as one other on the loom for some stupid reason. Connect them the wrong way round and the bike won't run, switch them back the right way round and the sender no longer works. Don't know why.
Good luck.
I took the engine out, removed the head and got a machine shop to fit a solid thread insert rather than a helicoil because the last thing I wanted was bits of helicoil in the engine without me knowing it when I changed a plug in the future.
Taking the engine out looks bad but it's just a long process that is pretty straightforward. However, one thing to watch is that you need to label the connection to the fuel level sender as it's the same one as one other on the loom for some stupid reason. Connect them the wrong way round and the bike won't run, switch them back the right way round and the sender no longer works. Don't know why.
Good luck.
Ready to drop engine tomorrow night.
I spoke to a guy from the 'superbike surgery' who specialises in inserting 'time serts' with the engine in place. But the thread on the thread on the spark plugs on the 954 are not compatible. He can put a helicoil in but would need the head off.
Another option was to put a time sert in for a slightly larger plug with would have baffled the new owner come the next plug change. He couldn't 100% guarantee it would work though.
I'll send the head off to an engine specialist. It also gives me the chance to give the bike a good tidy up, even though it was pretty clean to start with.
I spoke to a guy from the 'superbike surgery' who specialises in inserting 'time serts' with the engine in place. But the thread on the thread on the spark plugs on the 954 are not compatible. He can put a helicoil in but would need the head off.
Another option was to put a time sert in for a slightly larger plug with would have baffled the new owner come the next plug change. He couldn't 100% guarantee it would work though.
I'll send the head off to an engine specialist. It also gives me the chance to give the bike a good tidy up, even though it was pretty clean to start with.
dern said:
This is familiar, I think the threads weren't that great on those bikes. I bought my 929 brand new and I was the only one who removed and refitted the plugs and I know I didn't cross thread them. One of mine blew out at 70mph in 2nd taking the thread with it.
I took the engine out, removed the head and got a machine shop to fit a solid thread insert rather than a helicoil because the last thing I wanted was bits of helicoil in the engine without me knowing it when I changed a plug in the future.
Taking the engine out looks bad but it's just a long process that is pretty straightforward. However, one thing to watch is that you need to label the connection to the fuel level sender as it's the same one as one other on the loom for some stupid reason. Connect them the wrong way round and the bike won't run, switch them back the right way round and the sender no longer works. Don't know why.
Good luck.
Thanks Dern.I took the engine out, removed the head and got a machine shop to fit a solid thread insert rather than a helicoil because the last thing I wanted was bits of helicoil in the engine without me knowing it when I changed a plug in the future.
Taking the engine out looks bad but it's just a long process that is pretty straightforward. However, one thing to watch is that you need to label the connection to the fuel level sender as it's the same one as one other on the loom for some stupid reason. Connect them the wrong way round and the bike won't run, switch them back the right way round and the sender no longer works. Don't know why.
Good luck.
How much did u pay for the machine shop to sort the head ? I'm phoning for quotes tomorrow..
My money would be on someone bodging the thread previously by cross-threading a plug and then ratcheting it in as far as it will go.
Eventually it just lets go and pops the plug out!
I would try getting your phone in to take a photo first and then, if you can still see the start of the thread, a thread chaser to see if you can recover it; any decent engineer should have one the right size.
If it is totally bodged, then I don't see why it can't be helicoiled with the engine in the frame; you don't need a lot of room to do one (having done several aircooled VW engines over the years).
It's an alloy head so won't need a huge amount of force to do it and then you only need a vacuum cleaner and a long tube to clear out any swarf and it will run for 100k easily enough.
Eventually it just lets go and pops the plug out!
I would try getting your phone in to take a photo first and then, if you can still see the start of the thread, a thread chaser to see if you can recover it; any decent engineer should have one the right size.
If it is totally bodged, then I don't see why it can't be helicoiled with the engine in the frame; you don't need a lot of room to do one (having done several aircooled VW engines over the years).
It's an alloy head so won't need a huge amount of force to do it and then you only need a vacuum cleaner and a long tube to clear out any swarf and it will run for 100k easily enough.
WarnieV6GT said:
Thanks Dern.
How much did u pay for the machine shop to sort the head ? I'm phoning for quotes tomorrow..
It was a long time ago so I'm afraid I can't remember. It wasn't that bad I don't think. I didn't want to take the risk with doing it in situ as there is a small risk of small pieces of swarf getting down the sides of the piston.How much did u pay for the machine shop to sort the head ? I'm phoning for quotes tomorrow..
anonymous said:
[redacted]
Everything bolted to the engine so that what you end up with. It was good fun.I can't really remember but I think I took the back end off while the bike was suspended from the roof and then I lowered the engine to the floor. I don't think I had the means to lower the engine from the frame. It seemed logical at the time.
Edited by dern on Thursday 4th July 08:03
dern said:
anonymous said:
[redacted]
Everything bolted to the engine so that what you end up with. It was good fun.I can't really remember but I think I took the back end off while the bike was suspended from the roof and then I lowered the engine to the floor. I don't think I had the means to lower the engine from the frame. It seemed logical at the time.
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