Drive train "crashing" when engaged on a cold engine

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That's the difference. I don't ride anywhere that it gets cold enough to allow 5w to be advisable. I'm more of spending most of the time needing 15w50.
It isn't inadvisable to use a 5W in warmer temperatures, it just isn't necessary. It isn't "too thin" when temperatures are warmer - a 5W40 won't ever be less viscous than a straight 40 weight oil at any temperature. I think that in the earlier days of multigrade oils, viscosity breakdown was a bigger deal than it is today so perhaps a 5W would thin out sooner than a 10W or 15W? (Wild-ass guess) Not an issue with modern multigrade synthetic oils.

Where I live, the bike is off the road for most of four months (WINTER) and there may be another month when I might be riding at 10°C (50°F) or a bit lower when starting off in the morning. I prefer the 5W under those circumstances because it will flow faster in the time before the engine warms up. Once the engine is warm, it doesn't matter. To be honest, I would have no qualms about using the (relatively newly available) synthetic Rotella T6 15W40. I don't ride very often at temperatures where the lighter grade is really needed. I haven't up until now because it wasn't available in my region (the conventional T4 15W40 has always been available, but not the T6).

I would note that many car manufacturers are recommending 0W20 oils, even in markets with higher average ambient temperatures.

Just because of Yamaha's recommendation, I would shy away from a xxW30. Probably OK, but why chance it?
 
The 5W shouldn't be a problem - just means it doesn't get too thick and will flow better when cold. It doesn't make it too thin. I have always used a 5W40 (Rotella T6). Yamaha says 20W40 or 20W50 for my bike but there shouldn't be any issues - lower number before the "W" is better when temperatures are below 50° F but should never be lower viscosity than the oil is at operating temperature.

View attachment 5626
OTOH, the 30 part is lighter than recommended - at least in my manual.
Way back in 2010 the Gen2 specified 10w40. The Kawasaki shop is near me, so I use Kawasaki brand full synthetic. Yamaha shop is 25 miles away.
 
many car manufacturers are recommending 0W20 oils, even in markets with higher average ambient temperatures.
Riding in the north when cold, a multi-viscosity doesn't bother me, whether 2 or 4 wheels. That's why they make it! I agree with Ross. 25 - 95 degrees, it's all good. Nobody freaks about using their car in those temps.
 
Hi,
I have a 2015AF FJR1300. It was purchased by a friend as new, old stock, in 2017. He only did 3500kms in the 5 years before I brought it. It spent most of the time in storage. It was serviced every year, for the 5 years he had it, inline with the warranty requirements.
My problem is the drive train crashes into gear very loudly, when 1st gear is engaged while the engine is cold and on high idle. The problem does not exist when the engine is hot and idling at 1100rpm. I have changed the diff oil, engine oil and filter, hoping this would help however it hasn't. If I try to gently put it in gear you can hear cogs catching each other and chattering. I have tried dropping it into 1st gear abruptly and this generates a terrible crash sound.
The clutch is always smooth, no slippage or shuddering, whether the engine is cold or hot.
I am suspecting that because the bike sat for 2 years before being sold and that my friend hardly rode it, the clutch friction plates may have dried out and so are needing changing. Has anyone had this experience and found a solution? I'd really appreciate informed feedback on what may be going on here and how I can resolve it? My friend always warmed the bike up before riding it so he never experienced the issue I found.

A second observation is that when the bike starts cold, the idle rpm is about 1600rpm, which seems very high to me. Once warmed, the idle rpm is 1100rpm. Are these typical rpms for this bike?
Thanks everyone.
Don’t worry - you don’t know clunking until you get a Harley or an old style BMW. Just ride it.
 
Just read through this thread. The one thing not yet mentioned, but I assume a lot of people think when they hear the “kerchunk” (term worth googling on this forum) is that it is not your gears that are meshing violently to make that irksome noise. The gears on a motorcycle gearbox are known as a “constant mesh” (think there is still a forum member by that name) design. So the opposing gears are always fully meshed. They slide side to side on their splined shafts during engagement, and there are what is known as “dogs” that stick out laterally from the gear wheels that do the gear to gear engagements. They are much rougher, tougher, and less prone to chipping than the gears themselves.

My old 1st Gen 2005 kerchunked from the day I bought it until it left 100k miles older with it’s new owner on it. I tried varying oil many times, cleaned the clutch plates and oil soaked them, but nothing ever affected the cold shift kerchunk. During that time I often led groups of FJR riders on rides. I observed that they all did that at that time.

Imagine my surprise when I bought a brand new FJR in 2014 and that bike didn’t kerchunk even when cold. Every great once in a while it does make the noise if I rush into 1st, but what is most noteworthy is that most of the time it just snicks into gear.

My old ‘05 never snicked into first cold in it’s life. Even hot It was a non-snicker. I just got in the habit of always starting in gear once warm, as others have mentioned. I still always started in neutral cold so as not to put undue load on the wimpy starter motor.

No idea why my ‘14 doesn’t kerchunk. I did eventually put a slipper clutch in it, but it always snicked from day one even before the clutch upgrade. YMMV.
 
Hi,
I have a 2015AF FJR1300. It was purchased by a friend as new, old stock, in 2017. He only did 3500kms in the 5 years before I brought it. It spent most of the time in storage. It was serviced every year, for the 5 years he had it, inline with the warranty requirements.
My problem is the drive train crashes into gear very loudly, when 1st gear is engaged while the engine is cold and on high idle. The problem does not exist when the engine is hot and idling at 1100rpm. I have changed the diff oil, engine oil and filter, hoping this would help however it hasn't. If I try to gently put it in gear you can hear cogs catching each other and chattering. I have tried dropping it into 1st gear abruptly and this generates a terrible crash sound.
The clutch is always smooth, no slippage or shuddering, whether the engine is cold or hot.
I am suspecting that because the bike sat for 2 years before being sold and that my friend hardly rode it, the clutch friction plates may have dried out and so are needing changing. Has anyone had this experience and found a solution? I'd really appreciate informed feedback on what may be going on here and how I can resolve it? My friend always warmed the bike up before riding it so he never experienced the issue I found.

A second observation is that when the bike starts cold, the idle rpm is about 1600rpm, which seems very high to me. Once warmed, the idle rpm is 1100rpm. Are these typical rpms for this bike?
Thanks everyone.
Hi All,
I just want to report an update to my initial post. After following some advice from participants in this thread, I tried putting the bike in gear and clutch in, when cold, and then starting the bike. Every time I did this the bike walked forward as the motor started. This implied the clutch had friction in it. I replaced the clutch fluid and the same symptoms occurred. I have just had the clutch friction plates replaced and the mechanic found that there were 2 friction plates in the center of the pack that were partially dry, thus causing friction. This probably occurred during assembly, with the plates not being correctly soaked in oil, or as a result of sitting in the showroom for 2 years before it was sold. Either way the problem has been resolved. Thanks to everyone for your input.
 
I’m curious, what viscosity of oil is in the bike now with the new clutch, synthetic or dinosaur?
 
just had the clutch friction plates replaced and the mechanic found that there were 2 friction plates in the center of the pack that were partially dry, thus causing friction.
This has been a very common problem. Usually self-correcting (eventually), but the preferred solution is usually to remove the stack and soak the fibre disks in motor oil and possibly scour the steels with a Scotchbrite pad and oil. (Sometimes deposits on the fibre disks need to be removed as well) Lots of documentation on the forum about clutch soak. You can search on "clutch+soak" for a day's worth of reading. Speculation that the clutch disks were too dry during initial assembly...

Note: Rarely has it been necessary to replace the clutch disks - soaking is usually sufficient. Some people have commented that the bike's oil distribution doesn't spray enough on the clutch, but I have only heard of a couple of instances where someone had to do a second soak. I never had to do one in 450,000 km on two different Gen II FJRs.

From the original description, I had assumed that the OP was experiencing the characteristic FJR "kerchunk" of shifting into 1st from neutral with a cold engine. The clutch soak is clearly indicated if the bike surges forward when starting in 1st with the clutch pulled.
 
I’m curious, what viscosity of oil is in the bike now with the new clutch, synthetic or dinosaur?
Hi,
Synthetic 15W-40. The transmission still has the typical Ka-chuck when first put into gear cold. The replacement friction plates have got rid of the smash-crash it used to do and has solved the "walking" it did when started in gear and clutch in.
Cheers.
 
Mine does it too. This bike's gearbox loves to just randomly sound like someone's chucking 10mm sockets at a metal toolbox. I worried too until I heard a brand new 2022 one do it lol
 
Mine does this 1,500 to 2,000 miles after an oil change. I use 15w-40 synthetic. As such, I change oil when the clutch and transmission gets to feeling wonky. I would use 5w-40, but I'm a bit worried it's too light for the ring tension and valve train.
 
Mine does this 1,500 to 2,000 miles after an oil change. I use 15w-40 synthetic. As such, I change oil when the clutch and transmission gets to feeling wonky. I would use 5w-40, but I'm a bit worried it's too light for the ring tension and valve train.
Absolutely zero problem using a 5W40. All the "5" says is that it doesn't get too viscous (flows better) at lower temperature. Still provides sufficient protection when it is hot. I have used 5W40 for most of 450,000 km in two Gen II FJR. Never had any issues and never consumed significant amount of oil between changes.
 
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