4th gear issues R3R 2011

2011 R3R 34k miles. Riding this evening I first notice that it's not going into 5th gear properly. I often clutchless upshift without thinking about it, been doing it for years and it's second nature. Now bike doesn't snick into 5th like it normally does. So I'm mindful to make positive change using clutch. Ride a bit further then find it doesn't like going to 5th with the clutch either, like it's not going in properly first time. Bit further I find 4th gear shudders when under load accelerating, change to 5th it seems okay. Then jumped out of 5th at one stage under good load. Gears 1-3 seem okay. Now 30 miles later, the issue seems to only be with 4th gear. I have to skip it and while holding clutch in, go 3rd to 5th. 4th judders like it's slipping out then back in when under any load at all. I've done some thread research and worryingly seen some 4th gear dramas. Could i be lucky and it is the detent spring? I've not tried holding the gear lever up as I've only just researched and seen that test now I'm back home.

There are a pair of opposing bevel washers that act as a spring between 1st and 5th input gears, that stops 5th from spinning too freely and getting stuck in the way of the dogs on the side of 4th input when trying to engage 5th. If these washers were flattened out then it will become hard to get it into 5th.

Dogs could be rounded too..

The 4th output gear is known to be relatively weak, this why Robinson industries makes a billet one. Yours could be partially busted hence the juddering.

In any case these are examples and untimately guesswork until you split those cases
You will know more by simply dropping the sump first though.

My money is on rounded dogs .... but as Arto said you won't know for sure until you open it up

R-III-R Turbo said:

There are a pair of opposing bevel washers that act as a spring between 1st and 5th input gears, that stops 5th from spinning too freely and getting stuck in the way of the dogs on the side of 4th input when trying to engage 5th. If these washers were flattened out then it will become hard to get it into 5th.

Dogs could be rounded too..

The 4th output gear is known to be relatively weak, this why Robinson industries makes a billet one. Yours could be partially busted hence the juddering.

In any case these are examples and untimately guesswork until you split those cases
You will know more by simply dropping the sump first though.

Click to expand...

Thanks Arto. I'll drop the sump and look for bits of teeth down there.

1olbull said:

Continually shifting without using the clutch, especially under load without any electronic interrupter, is not a wise thing to do on any motorcycle or standard shift vehicle.
You have likely damaged your transmission, which will be a spendy repair.

Click to expand...

Clutchless upshifts are not done while under load. It's a manual replication of what an electronic quickshifter does and is a very common practice. Look it up and give it a try. Actually, on second thoughts, maybe not try it on a rocket with gear cogs made of cheese grommet

Martin-Brighton-uk said:

Clutchless upshifts are not done while under load. It's a manual replication of what an electronic quickshifter does and is a very common practice. Look it up and give it a try. Actually, on second thoughts, maybe not try it on a rocket with gear cogs made of cheese grommet

Click to expand...

I know of this and, respectfully, it is not a "common" practice without special mechanical or electronic assist.
Son of an Indian dealer from the 40-50s, I have been riding and racing motors as both as a professional and aficionado since 1950.
Drag racing back in the 60s I used a kill button to the gen/alt to momentarily kill while speed shifting. It was not a perfect system but worked for the occasional drag race event. Today's speed shifters are way more advanced, yet NOT a perfect system and definitely not recommended for continual daily use.
To compound this, our Rockets are not Japanese motors. They have weak transmissions and require riders to ALWAYS shift carefully and positively.
Just my opinion - FWIW.

Thank you for your opinion Sir.

Even with the qualification of your wealth of experience and expertise to lend weight to your opinion, it is just that. What might not be known or common for one person may be for other people. It would be a tad arrogant of someone think ones experiences and options constitute a world view.

In my case the special mechanical assist device is me rolling off the throttle sightly to stop engine load, while putting slight upward pressure on the gear lever, then it just snicks into the next gear. I don't do it at high revs, only when cruising, makes for a gentle change for a pillion.

FWIW I do agree with your final point and it's worth calling that out, that the Triumph Rocket gearbox is known to be weak and performing clutchless gear changes could exacerbate what is already a fault prone gearbox.

Be mindful that the Triumph Rocket gearbox is somewhat weak for it's application and performing clutchless gear changes, that may or may not be absolutely fine on a Japanese bike, could lead to gearbox failure.

Now off the barstool and back into the workshop...

I'll drop the sump and see what I find. If no lumps of metal or unexpected bits I may as well pull the front as it could well be engine out anyway. I'm reading with interest the other thread where the bike was stuck in 5th gear as that is giving me great technical pointers on how to proceed.

I had identical symptoms, unfortunately 1000 miles from home in St Louis, at rush hour, on the interstate on a blind curve. Carpenter said the circlip was backwards from the optimal installation and got pushed out of the groove, allowing the gears to roam around on the shaft. I believe Robinson also machines a deeper and or wider groove and installs a heavier circlip when they rebuild, along with back cutting dogs and a billet 4th gear. I have to agree with 1olbull, clutchless shifting is possible but neither common nor optimal. Good luck, I know that sick feeling when they lock up, there is even a special beer for the occasion.

What is it with the Rocket gearbox, abused many bikes over the last 46 years of riding and never broken a gear cluster yet, burned a few clutch plates but never had to ride a bike worrying wether the driveline will unexpectedly self destruct!
Been following the pink 201 bhp thread with great interest over the last few months and watching the videos of the bike being thrashed on the Dyno just amazed me how clunky and agricultural the gear change is.