Third gear has dissappeared?

[KevC]

Hi All,
Looks like Ive lost 3rd gear , happened very suddenly with no nasty noises or any other signs. Worked fine Monday morning on the way to work & had gone by Monday home time.
All the other gears are fine, does not slip out of any gear but putting it into 3rd is like a second neutral. (up or down the gearbox)
Guess its a major engine rebuild to get to this but would be grateful if any one can give a clue as to what it might be.
On a plus note the Ramair (UK company) foam filters I fitted a couple of weeks ago have completely cured the carb problems I was getting in the rain & damp with the K&Ns
Cheers Kev

 

[inxs]

- probably got it wrong........shift fork and receiver for 5th main gear ? shift fork could be bent to the left or worn on the rhs, the receiver worn esp on the rhs

- if youre having no problem shifting up and down then its unlikely to be the shift shaft or its lever and spring, nor is it likely to be the shift claw or its adjustment nor the stopper spring...could be worn shift cam and follower, or a combination of worn shiftcam, follower, shiftfork and reciever

- no metal bits in the sump ?

- pics of the filters fitted ?

 

[KevC]

Hi inxs
No problems shifting at all, just 3rd gear is missing. It will change into 3rd but you have no drive. Happened very suddenly with no sign of anything wrong prior to this.
Have now taken it out of use in case of metal parts in oil etc... but have not yet drained sump or looked in filters.
Kev

 

[jay760]

Sounds like the dogs on the 5th gear gone,

 

[jay760]

Shouldn't worry about it to much, it's been raining for a week, you can't ride it without getting soaked, been in the uk for a week it's rained every day!!!!!

 

[KevC]

The Great British summer, been riding in it all week & its in weather like this that proves how waterproof your waterproofs are. Mine, I discovered yesterday are not
Been using the XS as my every day bike for over 2 years, problem free, except when those dodgey carb boots split. Now using my VStar 1100 until the XS is sorted, Ill start the investigation this weekend

 

[KevC]

Sounds like the dogs on the 5th gear gone,

Looks like you were right on the money jay760. Drained the oil & checked the filters today, filters were ok but after feeling around in the sump discovered a drive dog. Tho Im happy to of discovered something before splitting the cases. Ive already started to get the motor out & will probably go for a full rebuild while Im there. Hopefully this is the drive dog off 5th gear because I have only seen replacements for 5th available

 

[KevC]

Got the engine out & made an engine stand out of some old angle, a big thanks to all those that provided the engine stand plans. Works a treat tho I added an inch to the heights of the mounts to give more clearance (read it somewhere, 5twins I think).
Ill try soad blasting the complete engine before stripping it down

 

[KevC]

Here's what I found when I stripped it down, all 3 dogs on 5th gear gone
Only found the one in the sump, so maybe the first 2 went years ago & it was just hanging on
At least it was 5th gear, which you can still buy new

 

[Punkskalar]

That is pretty rad. I've torn down several engines and still not found any broken transmission issues.

 

[member3480]

ME EITHER. I did 20 motors between last year and up to now and man now i know 10 pounds of boost from a turbo will blow that sucker to parts. Have to stay with the 5 pounds that i know will hold for street use.

 

[KevC]

Maybe not quite so rare as you may think, its happened to at least 3 people over at the garage since February this year

 

[jay760]

It's a recognized weakness in the gearbox, that's why mikexs used to keep the 5th gear cog which has the dogs for third gear, before they started making the new one with the higher ratio, I've had one with no third gear before.