Catastrophic Transmission Failure

[Txclassic]

Update

The initial transmission failure (the one where second gear parted company with the rest of the cluster gear and punched a hole in the engine block) - - occurred 3 days before the factory warranty expired.

Luckily, Triumph has good-willed the multiple repair attempts over the last seven months. I'm out gas, time, frustration, etc., but not the $6000 or more in parts/labor.

Summary:
1. Initial transmission failure June 2008. One third of second gear fractured and punched a 1/4" hole in the engine casing. Complete engine teardown, casing replacement, and upgrade kit installed. Bike returned mid September 2008.

2. Within 1 week, second gear would not mesh at all. Returned the bike back to the dealer. Dealer claimed Triumph sent them the wrong second gear dog ring. Engine tear down again and correct part installed. Repairs completed late November 2008 after an additional 1 week delay to fix the coolant leak from loose radiator hoses.

3. Within 1 week, the transmission was back to popping out of second gear under moderate to heavy acceleration. Shifter linkage adjusted per dealer's recommendations. No improvement. Back to the dealer in mid December.

4. Dealer calls on December 31 to say they could not find anything wrong with the bike during hard driving by both the service manager and owner of the dealership. I pickup the bike January 3. Within 5 miles of leaving the dealership, second gear craters again and would not mesh. I did not abuse the bike. Other gears work fine. Limp it right back to the dealer and insist the owner immediately take the bike for a test drive. He has no choice but to agree there is definitely a problem. No *&#! Sherlock. I've been saying that for the last 7 months!!

5. Called dealer yesterday to get an update. They will open up the engine again starting Tuesday, January 20. They estimate 30 hours of work, with an expected completion by Saturday, January 24. Service manager talked to Shell at Triumph (their senior service tech.). He explained the symptoms and Triumph thinks the circlip for second gear was installed backwards on the cluster gear. Under load, the beveled circlip will flex and/or pop out of the groove, causing partial/full disengagement.

Dealer admitted to even asking Triumph for some training assistance from the factory so they could get this right the next time. This clearly confirms my suspicion that this is a fixable problem, but ONLY if performed by competent technicians. My dealer just can't get it right.

They have offered a loaner. I don't care anymore. If the repairs are "successful", and I can get a decent trade in, I plan to get a Stratonliner S. (2 friends are on their second ones with over 200,000 combined trouble-free miles). A move to Louisiana is potentially in the future and I don't look forward to hauling it back to Houston (shorter trip than to the New Orleans dealership).

I sure will miss that awesome torque, but not the reliability headaches.

 

[Pig9r]

Thanks for the update. I don't blame you for wanting to walk away from this bike/brand.

 

[john.pilot@hotmail.com]

R3 Gearbox Failure Downunder

Hi Guys,

I written this thread elsewhere so its a bit different each time.

Mine is an 08 classic with 6,000 Kms on the clock and the gearbox turns to crap, jumping out of 1st, then 2nd, all at the wrong time under power.

This is a huge problem, if you have any shifting problems get it back to Triumph land as soon as you can as it is caused by, THE REAR OUTPUT SHAFT BEARING failing.
Yep the cage on the bearing starts to break up and your mainshaft gets taken out as well as some gears.

The problem in letting it go is that eventually the bearing will totally fail and you start breaking metal cases.

To their credit, the Triumph dealer said, "Oh yeh, we gotta kit for that" oh goody how about a recall or something but no they wait until the box breaks. The numbers are 1 in 3 and that climbing daily, the cost is thousands but, in good faith, Triumph are supplying the kits and the cost to me for the over haul was nothing....

Here in Aus, this problem is common and well known by the dealers, but they are not saying anything!!!

If you have any gearbox doubts, jumping outa gear, you will not fix it by;
1 Praying
2 Doing banana skin transplants in your oil
3 By hitting the gear lever harder
4 By kicking your sheep (dog)

Get onto it!!!!!!!!!!!!

 

[HeR3tic]

Thanks for the update. I don't blame you for wanting to walk away from this bike/brand.

Can't blame anyone with such bad luck to berate the FBG. The same lemons abound everywhere. One person's bad day on the assembly line leads to many more problems. I suppose there's a lesson there.

 

[Madal]

Gearbox Failure

Clearly the gearbox on some Rockets is an issue. My 2005 did the same second gear thing and was fixed under warranty. (13000km). Now its done 25000km and yep its doing it again so we are about to pull it apart.
Does anyone know what the cause of the problem is and if there is a fix for it ?
Due to the horsepower my bike makes (250hp) will look at under cutting the main gears but there must be and underlying cause given the same issue occurred with 140Hp so its not just a case of too much grunt.

cheers

Mike

 

[Sidecar Flip]

I'm very grateful that I have Tomo and Pigger for advice and guidance. That was how I wound up with Baxter's in Marne, Iowa. It might be a 625 mile commute but I feel strongly that I won't be experiencing any more problems now that the qualified and experienced technicians at Baxter's have rebuilt my internals.

You can read about my adventures in the thread I've started under common issues. Of course I don't have the bike back yet, but I'm very confident that it will be trouble free from here on out.

 

[Txclassic]

My dealer is almost as frustrated as I am. With the exception of the teardown for the engine block hole from second gear fracturing, ALL the other teardowns have shown NO signs of damage, metal fragments, bent forks, broken circlips, busted springs, or any other visible cause of the problem.

On this last repair attempt (hopefully done this week), Triumph confirmed correct assembly orientation of all the parts. The dealer opted to replace a few circlips and replaced the shifter shaft.

I've studied this thing from every photo available. Thanks to all that have done their own rebuilds and documented the effort.

Pages 8.2 thru 8.10 of the service manual will be useful during this discussion.

Based on the assembly details, basic mechanical understanding, and an engineering mind that doesn't know when to leave well enough alone, I have come up with a 4-beer theory for my transmission problems:

1. If second gear or the dog ring is disengaging under acceleration load, then there is a reaction force making this happen PLUS an insufficient amount of opposing force to hold it in engagement.

2. The thrust load imposed from torque on the helical cut gear is the most likely culprit for disengagement force. A secondary factor could be slop in the assembly and/or bad bearings that are exacerbated under acceleration. The thrust load is unpreventable. The cluster gear assembly, forks+guides, and selector drum are all needed to keep the gear engaged in spite of this thrust load. In fact, the upgrade kit attempts to remedy the problem by shimming the clearances in the whole assembly.

3. If the selector drum (the cylinder with the grooves for the fork guides) is indexed to the proper position, then the fork guide will rest in a flat spot on the groove. Thrust load on the shifter forks imposed by the engaged gear will be resisted by the fork and its guide pressing perpendicular to the groove in the shift drum. Things will stay in place and all is well. No rotational force on the selector drum will be present.

4. However, if there is slop between the shifter fork and the selected gear and/or the fork guide is resting in a sloped portion of the groove on the selector drum, then the reaction force will make the gear+fork slide along the path of least resistance. If the shifter drum has not fully indexed to the flat resting spot for the fork guide, then bad things are going to happen. Acceleration load will try to force second gear back to where it came from (toward neutral). Since the transmission has the longest throw to accomplish going from 1-N-2 in one single shift actuation step, this is the most likely of the two alternatives. Also, tor this to happen, the selector drum would have to be free to rotate out of position.

5. If the shifter drum is "over indexed", then the other possibility is the thrust load will try to partially shift toward 3rd gear.

6. OK great. But what could be keeping the shifter drum from being properly indexed to the proper shift position for 2nd gear and what could allow it to rotate out of the selected shift position? I propose a couple of possibilities: a) The shift linkage and internal geometry are inadequate for the amount of throw required to fully engage a 1-N-2 upshift or 3-2 downshift. b) The detent wheel, springs, and/or selector shaft bearings are allowing the selector drum to rotate out of its intended position. c) the indexed positions on the detent wheel are not precise enough to guarantee the proper position of the selector drum for the 2nd gear shift (up or down).

7. This selector drum assembly is very complicated. The detent arm and detent wheel, along with the gear change return spring ensure that each shift indexes the selector drum to the appropriate position, and keeps it there until you grab the next gear. The detent wheel is registered to the selector drum shaft by a little alignment pin and recess in the detent wheel. This assembly is NOT intended to bear any rotational forces imposed on it from the shifter forks trying to rotate the selector drum. It is merely there to ensure the correct amount of travel on each shift attempt. Full travel of your foot on the shifter linkage is supposed to translate into full engagement of the selector drum to the next shift position (and no further).

8. If the selector drum is not fully indexing to full 2nd gear engagement, then there is a problem with the linkage geometry or the detent wheel assembly, or slop in the whole setup.

9. When the selector shaft is not fully indexed to the full shift position for 2nd gear, the detent wheel and detent arm spring bear the mechanical load of holding the selector drum in position as all the things mentioned above conspire to force second gear out of engagement. The end result is a bent detent arm, broken springs, broken detent wheel pin, and other bad stuff.

I propose the following test in the shop to see if things are still broken before wasting 8 months of your life fighting with your dealer and Triumph:

1. After the engine internals are fully assembled and the casing halves are torqued down, slide the clutch basket onto its splined shaft.

2. Attach the output shaft, differential assembly and rear wheel to the engine.

3. With a strap wrench around the clutch basket and the transmission engaged in 2nd gear, block the rear wheel from rotation. Apply 140 ft-lbs of torque in the right direction to the clutch basket while the rear wheel is held in place. If she doesn't slip out of gear, then repeat this 50 times after simulating 1-N-2 upshifts and 3-2 downshifts.

4. Proceed with bike assembly only if the transmission does not slip.

Well, that 's my story and I'm stickin' to it. It's been fun and it's taken more than 4 beers to spew all this crap out, but maybe it will help someone with a better dealer diagnose the real problem.

Thanks for reading this far.

Txclassic.

 

[Kmutt]

**** TX now my day is over!!!
Thanks I rather enjoyed reading that!!
Good luck...I pray it turns out well!

mutt

 

[Sidecar Flip]

This is scary.....

........and I presume that's why the upgrade kit includes the necessary thrust washers as well as new shifting forks. Probably why the shifter detent spring has been upgraded to one of more stout tension and the retainer bolt is improved and is self locking.

Though I haven't seen the parts yet, I would assume that my shift forks had little wear because I very rarely accelerate had through the gears so I don't impose the thrust load that one would with hard acceleration. All helical cut gears inpose side thrust. It's the nature of the design. They are quieter and the contact patch is greater than other types.

Finally, don't discount the fact that the synchromesh rings themselves, negate quite a bit of the side thrust generated by the helical cut gears. The synchromesh rings are also upgraded with thicker intermediate washers to bring the gearsets up to meshing speed more quickly as well (I was told).

If, Triumph is replacing the thrusts and shimming the gearsets (besides the TDU output bearing) and all the rest of the internal upgrades, then, one has to assume that, at some point, Triumph is expecting a very high failure rate with units already in the field prior to the upgrades being instituted at a factory level.

Of course, when Triumph actually instituted the kit upgrades on the assembly line is all conjecture because Triumph either chooses not to document line changes or prefers to keep that data secret.

 

[The Beast]

Help !!!

That is one scary thread!
Occasionally my 08' pops out of 1st gear, to neutral, on initial clutch release.
Here's the drill.
The motor is running in neutral, I put it in 1st, I ease off the clutch, the gear "pops" to neutral, I "stomp" the shifter, (to forcefully put it in 1st), it engages to 1st, and I'm on my way. I have no other issues.
I have assumed that, without thinking, that I'm just not putting enough pressure on the shifter initially.
What do you guys think?
I have about 300 miles on my "new" 08.
Thanks,
Beast