Tranny (shifter) bokerforked (Found: star cam broke off the shift drum!)

Constant Mesh · Sep 14, 2014

Would be interesting to see the dogs for 1st gear. Those take a beating when you're idling in neutral, sitting still and then you hammer it into 1st gear. The bike will often jump forward a bit as the dogs connect. One gear spinning a bit, the other gear motionless.

It appears that Yamaha has evolved over the years about how many dogs they use on the gears. From the drawings and some photos I've seen the FJR has several gears with three dogs and six slots in the adjacent gear.

Yamaha's newer designs often used a five dog configuration with five slots in the adjacent gear.

More slots would seem to offer better shifting.

RossKean · Sep 14, 2014

I am astonished with the difference in wear between the two transmissions. I wonder if the differences are simply due to miles, riding style/habits or if there was something fundamentally wrong with yours from day one? I would love to see what mine looks like after 123,000 miles - hope I never have the opportunity (or need) to have a look at it!

Constant Mesh · Sep 14, 2014

There is a need for an oil filter after all. To capture the gear and fork metal.

I wonder how much material is thrown off the clutch as it wears away over time?

wfooshee · Sep 14, 2014

My bike has just over 90,000 miles, and I bought it with 41,000. Oil changes are performed religiously using Rotella 15w-40. I even joked with my brother yesterday that I should start an oil thread. I don't know the mileage of the other engine. If memory serves, that's the engine the forum found for Patriot after his cam chain tensioner failure, which ended up eating a crankshaft bearing.

I have already got the entire transmission from that engine sitting in mine, now waiting on the crankshaft bearing bolts to arrive so I can start screwing stuff back together. The first-gear dogs don't look bad at all, no appreciable difference between the two sets.

I am not an aggressive rider, and I don't do clutchless shifting. I have experienced false neutrals, not frequently, from 3rd to 4th, but I'm leaning towards calling that an effect and not a cause. The only thing I can come up with that makes it "my fault" is that I live rather close to work, less than three and a half miles, so even with a breakfast detour for a chicken biscuit once in a while, the bike is barely getting warmed up in the mornings. Even before my employer moved to this location, the previous ride was just under five miles.

ionbeam · Sep 14, 2014

wfooshee said:
...I am not an aggressive rider, and I don't do clutchless shifting. I have experienced false neutrals, not frequently, from 3rd to 4th, but I'm leaning towards calling that an effect and not a cause...

Do you let the toe of your boot/shoe rest on the shifter? Don't be too quick to say no, it could be a subconscious thing to do so you may not really know until you can ride your resuscitated FJR. I see people hit cruising speed and rest their foot on the shifter which keeps pressure on the shift fork.

Constant Mesh · Sep 14, 2014

While you've got it apart you might as well change the gear ratio on the middle drive gear set and reduce your engine speed about 3% for all the gears.

You'd have to replace the gear in your photo labeled "middle gear drive" with one from an '06 or later. I suppose you'd have to replace the other gear in that set on the middle drive shaft too. Although that last gear has the same number of teeth as before -- it didn't change on the '06. Maybe the teeth on that gear are cut a little different for the '06 and after. I don't know.

Constant Mesh · Sep 14, 2014

Do you see any appreciable wear on the fingers of the spring-loaded damper cam doodads on the middle drive shaft? I've wondered if those parts get wallowed out a bit over several years of use. I don't know how much of the drive line slack/play originates in the spring-loaded damper?

wfooshee · Sep 14, 2014

Middle gear stuff looks OK to my eye. Not really interested in changing that ratio, as I'm not even remotely interested in disassembling the middle gear assembly.

As for resting on the shifter, it's a definitive no. I ride with ball of the foot on the pegs, I have to move my foot forward to operate the shifter.

ionbeam · Sep 14, 2014

The middle gear is what the VSS sensor gets its signal from, the Gen I ECU won't be expecting what it will be getting.

Constant Mesh · Sep 14, 2014

Nah! The VSS sensor is looking at the gear on the middle drive shaft. The number of teeth on that gear didn't change in '06. It's always had 35 teeth, unless something changed in the '13 and '14.

HotRodZilla · Sep 14, 2014

FWIW, that was super interesting and actually made sense. I have never understood how the gears on these things work. Right now, that is useless information, and I hope it stays that way, but if it doesn't, at least I have an idea. Lol...Thanks!!

'Zilla

wfooshee · Sep 15, 2014

Something just clicked in my head about that shift fork wear and the accompanying wear on the slot of the gear wheel that it rides in. With that beveling of the fourth gear dogs, any thrust while in fourth gear now has a sideways vector on that part, pushing it back towards its neutral position, with the only thing retaining it being the position of the shift fork. The shift fork became a thrust bearing, which don't s'posed ta happen.

Makes sense explaining the shift fork wear, but where the hell did the beveling come from??!??!??!!

TownsendsFJR1300 · Sep 15, 2014

An interesting link somewhat related to your issue;

https://plus.google.com/photos/114258258571800441805/albums/5154166965616954081?banner=pwa

Also, re the beveling of the gear cogs.

Its not unusual for that wear to occur. One shop I frequented had a bike with transmision issues, junmping out of gear.

Besides replacing the worn gear, they back cut the cogs so the more HP / torque you put to that gear, the harder the gear/cog stayed in its appropriate spot...

Constant Mesh · Sep 15, 2014

For the '08 model they introduced a new design for the 4th gear parts. Don't know why they changed it -- easier shifting, stronger dogs, more dogs, etc. From the parts diagram it appears they went to five dog, five slot gears.

It's interesting they decided to make this particular change after so many years of production.

I seem to recall this change was highlighted in the "Changes for '08" list on the Yamaha site.

wfooshee · Sep 17, 2014

My crank bearing bolts finally arrived and I've got the sealant on order for the case halves. That stuff is valuable!!! (Apparently.)

8.8-ounce tube (250 grams) is anywhere from 25 to 55 dollars! Yamaha's part number for it in the service manual Googled to Three Bond 1215, silicon liquid gasket. Probably only need an ounce or less out of that tube..... My brother told me I'll probably need ten ounces.

Got some cleaning to do first to get oil off of the surfaces.

I won't be riding this weekend, but I should be by the end of the month!!!!!

rPGoatBoy · Sep 17, 2014

Yamabond 4 is probably close enough to the same stuff, cheaper, and more readily available. It's what I used to glue my case halves together.

HotRodZilla · Sep 17, 2014

Why not just high temp RTV? What's so special about the expensive stuff?

wfooshee · Sep 17, 2014

HotRodZilla said:
Yamabond 4 is probably close enough to the same stuff, cheaper, and more readily available. It's what I used to glue my case halves together.

Ya know, one of my books says Yamaha bond #1215 and gives a number, which I Googled and it crosses to ThreeBond 1215, but my other book says "Quick Gasket" and gives a number, which Googles to Yamabond 4.

****. It's only money, right?

Ounce for ounce it's not really cheaper, but Yamabond 4 comes in smaller tubes!

TownsendsFJR1300 · Sep 18, 2014

I just (within 3 months) just purchased a 9 oz tube of Yamabond 4 (on Amazon I believe). Wasn't that expensive.

It does seem a little thinner than the original product from years ago. I've used the Yamabond on several different

brand engine cases, never had a leak. IMO, spending a little extra for the specified product is well worth it.

You don't want to have a "do over" should you develop some leaks...

wfooshee · Sep 20, 2014

Transmission shafts are back in the case, but still waiting on sealant and torque angle gauge to arrive, so no further reassembly yet. However, I figured I'd dig out the video mode of my dSLR and have some fun. I shot the shifter ratchet in action on the star cam, which is actually kind of dull, but useful if you've never known what happens when you kick the shifter up or down. After that, you see the axle shafts in action through the ratios. 4th and 5th are harder to see because that shift happens in the input shaft which is almost hidden under the output shaft. The big gear at the top left is the output to the middle gear shaft, and you see it get faster through the shifting. The shift drum, turned by the ratchet action on the star cam, is at the bottom of the frame.

I turned the input shaft with one hand (where the clutch basket belongs) and operated the shifter arm (the same arm the pedal actually links to) with the other hand.

Point of view, keeping in mind the engine is upside-down, is looking upward from the road surface in front of the rear wheel.

For best viewing click on the Youtube logo to watch it on their site, then select 1080 and full screen. There's no sound, as I had lots of noisy fans in the garage, and it wasn't worth trying to "narrate" over the noise.

Tranny (shifter) bokerforked (Found: star cam broke off the shift drum!)

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