An impact in a chuckhole or frost heave not solid enough to leave any real memory of it can be more than enough to bend a rim. Been there done that. I have also had the minimum wage monkey at the tire shop bend a rim as well. Of course they claim that there is a zero chance that their highly underskilled highly underpaid staff is responsible. Both times the bike thumped hard enough at 95 to 100 that my glasses were shaking.
High Speed Thumping
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Kirrilian
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I have considered this as well, I have experienced things that resonate and a certain RPM in other areas but my assumption is that if so other people would have the same issue and you are the only one that has said they have the same problem. I dunno, it is befuddling.
I will give some of the suggestions a try this weekend, particularly checking to see if the rims are true or not. I have a feeling if it is anywhere it is there.
rhody
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I have had my 05 since early in 06 and had only the OEM Metzlers and Pirelli Diablo Strada's on for rubber, almost always ride without side bags, however, when I do ride with bags and approach the magic 100 - 110 mark, notice what I call a high speed oscillation. This DOES NOT HAPPEN without bags on, no matter what speed/wind conditions, etc.... The reason I mention the word oscillation, is that one man's adjective could be substituted for another. It was never bothersome enough to be considered unsafe, just annoying. I attribute the oscillation to unstable airflow behind and around the saddlebags. I also tend to be much more sensitive riding the bike than a cage, my safety senso-meter goes up by at 50%, and I know that this factor alone has contributed to my survival on roads crammed with unsafe and plain stupid cagers.
As mentioned by other posters this could be from your windscreen setting and bags. I did experiment with standard yami screen up down and middle settings with bags on and could never rid myself of the oscillation. The only condition I think that would be unsafe while riding at speeds like this are occasional gusty side winds, because they tend to exagerrate the oscillation, turning it into what I call a mini tank slapper.
To briefly relate a wind related speed scare incident, on a deserted large tree lined flat smooth section of road I briefly approached 9000 rpm in fifth gear, you do the math for speed, and having cleared the trees (which acted as a wind buffer) and was hit with gusty side winds hitting the left front of the bike at a 45% or so degree angle, I was coming off the throttle smoothly at the time as well and much to my horror the bike began walking on its own to the right of the road. It got my full attention. I corrected with left lean but because of the gusts it was unnerving, and applied gentle rear brake followed by the front, once I was below 100 or so I was fine. It gave me a moment for pause and added another environment factor to consider when tracking at speed.
Enough said, good luck on trapping and hopefully eliminating your demon.
As mentioned by other posters this could be from your windscreen setting and bags. I did experiment with standard yami screen up down and middle settings with bags on and could never rid myself of the oscillation. The only condition I think that would be unsafe while riding at speeds like this are occasional gusty side winds, because they tend to exagerrate the oscillation, turning it into what I call a mini tank slapper.
To briefly relate a wind related speed scare incident, on a deserted large tree lined flat smooth section of road I briefly approached 9000 rpm in fifth gear, you do the math for speed, and having cleared the trees (which acted as a wind buffer) and was hit with gusty side winds hitting the left front of the bike at a 45% or so degree angle, I was coming off the throttle smoothly at the time as well and much to my horror the bike began walking on its own to the right of the road. It got my full attention. I corrected with left lean but because of the gusts it was unnerving, and applied gentle rear brake followed by the front, once I was below 100 or so I was fine. It gave me a moment for pause and added another environment factor to consider when tracking at speed.
Enough said, good luck on trapping and hopefully eliminating your demon.
Kirrilian
Well-known member
Wow, I never would have considered the saddle bags causing this. I ALWAYS have them on but what you're saying does make sense. I am going for a ride tomorrow and I'll find one of those nice straight country roads with nothing around and give it a go without the saddle bags. Also, on the wind, I used to live in OK and I distinctly remember the wind being so bad that I was leaned over while going straight, pretty unnerving, I couldn't imagine doing that at the speeds we are talking about. Thanks for your input, I'll try this first since I'm lazy and dont feel like doing all the crap to check the wheelsI have had my 05 since early in 06 and had only the OEM Metzlers and Pirelli Diablo Strada's on for rubber, almost always ride without side bags, however, when I do ride with bags and approach the magic 100 - 110 mark, notice what I call a high speed oscillation. This DOES NOT HAPPEN without bags on, no matter what speed/wind conditions, etc.... The reason I mention the word oscillation, is that one man's adjective could be substituted for another. It was never bothersome enough to be considered unsafe, just annoying. I attribute the oscillation to unstable airflow behind and around the saddlebags. I also tend to be much more sensitive riding the bike than a cage, my safety senso-meter goes up by at 50%, and I know that this factor alone has contributed to my survival on roads crammed with unsafe and plain stupid cagers.
As mentioned by other posters this could be from your windscreen setting and bags. I did experiment with standard yami screen up down and middle settings with bags on and could never rid myself of the oscillation. The only condition I think that would be unsafe while riding at speeds like this are occasional gusty side winds, because they tend to exagerrate the oscillation, turning it into what I call a mini tank slapper.
To briefly relate a wind related speed scare incident, on a deserted large tree lined flat smooth section of road I briefly approached 9000 rpm in fifth gear, you do the math for speed, and having cleared the trees (which acted as a wind buffer) and was hit with gusty side winds hitting the left front of the bike at a 45% or so degree angle, I was coming off the throttle smoothly at the time as well and much to my horror the bike began walking on its own to the right of the road. It got my full attention. I corrected with left lean but because of the gusts it was unnerving, and applied gentle rear brake followed by the front, once I was below 100 or so I was fine. It gave me a moment for pause and added another environment factor to consider when tracking at speed.
Enough said, good luck on trapping and hopefully eliminating your demon.
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Kirrilian
Well-known member
Ok, I have done some more testing and I think we have a direction to go to try and figure this out.
Things I've tried:
I rode without the saddlebags today (the bike looks so... NAKED like that) and experienced the same issue.
I pulled the clutch in and it stopped but I'm not sure if it is because the bike slowed down or because the engine was disengaged.
It gets faster the faster you go.
Not sure what to do from here, it is making me really uncomfortable to go those speeds now not knowing if something may go south and end up killing me...
Things I've tried:
I rode without the saddlebags today (the bike looks so... NAKED like that) and experienced the same issue.
I pulled the clutch in and it stopped but I'm not sure if it is because the bike slowed down or because the engine was disengaged.
It gets faster the faster you go.
Not sure what to do from here, it is making me really uncomfortable to go those speeds now not knowing if something may go south and end up killing me...
Kirrilian I know exactly what your hearing because my 06 does the same thing north of 110.
I first noticed it last year. Mine does it under load, if I back out of the throttle slightly so the
bike is just maintaining speed or slightly loosing speed the thumping goes away, full throttle
and it comes back. It seems to be the worst after a long period of high speed riding.
Since I first noticed this I've been through several sets of tires. Rims are straight and true.
I've had the drive shaft U joint out several times to lube the splines and all looks good.
Wheel bearings good, everything torqued properly
It is very unnerving to say the least. Hope all the good people here can shed some light
on this.
Frank
I first noticed it last year. Mine does it under load, if I back out of the throttle slightly so the
bike is just maintaining speed or slightly loosing speed the thumping goes away, full throttle
and it comes back. It seems to be the worst after a long period of high speed riding.
Since I first noticed this I've been through several sets of tires. Rims are straight and true.
I've had the drive shaft U joint out several times to lube the splines and all looks good.
Wheel bearings good, everything torqued properly
It is very unnerving to say the least. Hope all the good people here can shed some light
on this.
Frank
rhody
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Kirillian and especially Frailer, what you just said about the symptoms, under load in excess of 110 mph leads me to believe there is an ever so slight primary imbalance in your engine, or at the very least some loose tolerances probably made worse by heavy throttle and bearings (probably crankshaft) slightly out of spec.
I think Frailer is on to something because he says it is worse when load is put on the engine. It stands to reason that as the bearings and their races are spun harder if there is slop this could induce the thumping.
Try this for an experiment, when it thumps at speed, under load or cruising in 5th, note the rpm exactly, as long you are less than about 125 mph, about tops in 4th gear, down-shift from 5th into 4th which should raise the rpms about 750 or so. If the problem gets better, ceases or almost goes away, you have found your problem. Then, in 4th go the same exact rpm as you did in 5th, note the feeling, now drop the rpm's in 4th 750 or so and if the thumping comes back, it may be an isolated secondary harmonic vibration. For that matter, spin the engine at the same rpm in 3rd and 2nd as well, and again note the thumping. If the feeling is identical in 2nd - 5th gear, then for sure it is probably not the drive shaft, or rear drive gears and joints, and probably not the tires and wheels either. If what I am suggesting is true, it makes sense you don't feel it in 2nd - 4th gears because you don't stay in them long enough to notice. The experiment should prove it one way or the other.
If this is a Yamaha assembly quality control problem there has to be more bikes out there with this problem, considering how many tickers and ignition failures I have read about over the past two years. This problem can't be isolated to just a few bikes with a company with that kind of quality track record.
I doubt Yamaha would step up to the plate and fix it because if they did and the media got hold of the conditions in which it occurred a whole slew of safety questions (a-hem the hauling-*** kind, no offense Haulin-Ashe) would arise.
Lastly, as a possible contributor to the problem, I bought two cheap car tires a few years ago, that were ever so slightly out of round, put them on the front of my car and noticed a vibration, thumping about about 75 mph, took them back, spun balanced them and with a screw driver noticed they were both out of round about 1/10 of an inch. My solution, put them on the rear where the vibration is not as noticeable. Going to change all 4 this fall with good tires and I should be fine.
If I find a Leo free safe desolate area I will try the 5th - 2nd gear experiment I suggested, varying rpms and load with my 05 paying close attention to what I feel and let you know what I find.
If there are any German forum members out there who regularly ride the autobahn at these speeds and have or have not noticed this, please, contribute your experience, and theories to this thread.
Sorry for being so long winded, but I like a tough problem, this is a beauty...
:huh:
I think Frailer is on to something because he says it is worse when load is put on the engine. It stands to reason that as the bearings and their races are spun harder if there is slop this could induce the thumping.
Try this for an experiment, when it thumps at speed, under load or cruising in 5th, note the rpm exactly, as long you are less than about 125 mph, about tops in 4th gear, down-shift from 5th into 4th which should raise the rpms about 750 or so. If the problem gets better, ceases or almost goes away, you have found your problem. Then, in 4th go the same exact rpm as you did in 5th, note the feeling, now drop the rpm's in 4th 750 or so and if the thumping comes back, it may be an isolated secondary harmonic vibration. For that matter, spin the engine at the same rpm in 3rd and 2nd as well, and again note the thumping. If the feeling is identical in 2nd - 5th gear, then for sure it is probably not the drive shaft, or rear drive gears and joints, and probably not the tires and wheels either. If what I am suggesting is true, it makes sense you don't feel it in 2nd - 4th gears because you don't stay in them long enough to notice. The experiment should prove it one way or the other.
If this is a Yamaha assembly quality control problem there has to be more bikes out there with this problem, considering how many tickers and ignition failures I have read about over the past two years. This problem can't be isolated to just a few bikes with a company with that kind of quality track record.
I doubt Yamaha would step up to the plate and fix it because if they did and the media got hold of the conditions in which it occurred a whole slew of safety questions (a-hem the hauling-*** kind, no offense Haulin-Ashe) would arise.
Lastly, as a possible contributor to the problem, I bought two cheap car tires a few years ago, that were ever so slightly out of round, put them on the front of my car and noticed a vibration, thumping about about 75 mph, took them back, spun balanced them and with a screw driver noticed they were both out of round about 1/10 of an inch. My solution, put them on the rear where the vibration is not as noticeable. Going to change all 4 this fall with good tires and I should be fine.
If I find a Leo free safe desolate area I will try the 5th - 2nd gear experiment I suggested, varying rpms and load with my 05 paying close attention to what I feel and let you know what I find.
If there are any German forum members out there who regularly ride the autobahn at these speeds and have or have not noticed this, please, contribute your experience, and theories to this thread.
Sorry for being so long winded, but I like a tough problem, this is a beauty...
:huh:
E1Allen
Youngster
Yeah well he takes his bike to the track and that is where he notices the problems, obviously he would not drive that fast on the road...
Eric
rhody:
Thanks for the interesting diagnosis.
I can kind of see where you're coming from with that idea. When the weather gets better (could be a long time) I'll see what I can come up with.
Thanks for input
Frank
Try this for an experiment, when it thumps at speed, under load or cruising in 5th, note the rpm exactly, as long you are less than about 125 mph, about tops in 4th gear, down-shift from 5th into 4th which should raise the rpms about 750 or so. If the problem gets better, ceases or almost goes away, you have found your problem. Then, in 4th go the same exact rpm as you did in 5th, note the feeling, now drop the rpm's in 4th 750 or so and if the thumping comes back, it may be an isolated secondary harmonic vibration. For that matter, spin the engine at the same rpm in 3rd and 2nd as well, and again note the thumping. If the feeling is identical in 2nd - 5th gear, then for sure it is probably not the drive shaft, or rear drive gears and joints, and probably not the tires and wheels either. If what I am suggesting is true, it makes sense you don't feel it in 2nd - 4th gears because you don't stay in them long enough to notice. The experiment should prove it one way or the other.
Thanks for the interesting diagnosis.
I can kind of see where you're coming from with that idea. When the weather gets better (could be a long time) I'll see what I can come up with.
Thanks for input
Frank
Try this for an experiment, when it thumps at speed, under load or cruising in 5th, note the rpm exactly, as long you are less than about 125 mph, about tops in 4th gear, down-shift from 5th into 4th which should raise the rpms about 750 or so. If the problem gets better, ceases or almost goes away, you have found your problem. Then, in 4th go the same exact rpm as you did in 5th, note the feeling, now drop the rpm's in 4th 750 or so and if the thumping comes back, it may be an isolated secondary harmonic vibration. For that matter, spin the engine at the same rpm in 3rd and 2nd as well, and again note the thumping. If the feeling is identical in 2nd - 5th gear, then for sure it is probably not the drive shaft, or rear drive gears and joints, and probably not the tires and wheels either. If what I am suggesting is true, it makes sense you don't feel it in 2nd - 4th gears because you don't stay in them long enough to notice. The experiment should prove it one way or the other.
rhody
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Frank,
I have an 05 FJR, a Gen 1 bike, stock except for a K&N air filter and it looks like your bike is an 06, a Gen 2, with if I am correct slightly taller gearing. I didn't have much time at this speed to compare the feeling, but here is what I did. Started at 60mph in 3rd, pinned it to 110mph and then short shifted to 5th. Noticed that the rpms were about 6500 or so, right in the meat of the torque curve. I didn't notice a thumping, but I did notice that the engine didn't seem smooth and happy at this speed/rpm. Backing off throttle I noticed the popping associated with unburned fuel. I only held that speed about 10 seconds or so. Then I shifted to 4th at 6500 rpm, then 3rd, then 2nd all at the same rpm, 6500. I didn't notice any thumping whatsoever, my engine is happier above 7000 rpm. Things seem much smoother, the raspiness is reduced.
I looked up at a dyno chart here: https://www.fjr1300.info/chart.html (an 02 model) you will notice that torque peaks at about 6750 rpm or so, dead nuts on where my engine did not seem very happy. It stands to reason that if the torque peaks at this rpm, then the loads on the crankshaft bearings loads should be maxed out when this rpm is reached and then pushed through. If the thumping frequency in lower gears (4th - 2nd) on your bike is still present, lower than it is in 5th gear then I think you have found the answer. If it is not present at all, then it could be rims and or tires, and possibly the shaft drive system consisting of the shaft assembly with the universal gear on the output side of the engine. I would suspect things are not tight with the shaft itself, and the shaft itself vibrate up and down along the axis of the bike.
Like I said earlier, I am surprised more riders are not reporting this problem. I would be interested to know what you find when you run this test yourself.
Rhody
I have an 05 FJR, a Gen 1 bike, stock except for a K&N air filter and it looks like your bike is an 06, a Gen 2, with if I am correct slightly taller gearing. I didn't have much time at this speed to compare the feeling, but here is what I did. Started at 60mph in 3rd, pinned it to 110mph and then short shifted to 5th. Noticed that the rpms were about 6500 or so, right in the meat of the torque curve. I didn't notice a thumping, but I did notice that the engine didn't seem smooth and happy at this speed/rpm. Backing off throttle I noticed the popping associated with unburned fuel. I only held that speed about 10 seconds or so. Then I shifted to 4th at 6500 rpm, then 3rd, then 2nd all at the same rpm, 6500. I didn't notice any thumping whatsoever, my engine is happier above 7000 rpm. Things seem much smoother, the raspiness is reduced.
I looked up at a dyno chart here: https://www.fjr1300.info/chart.html (an 02 model) you will notice that torque peaks at about 6750 rpm or so, dead nuts on where my engine did not seem very happy. It stands to reason that if the torque peaks at this rpm, then the loads on the crankshaft bearings loads should be maxed out when this rpm is reached and then pushed through. If the thumping frequency in lower gears (4th - 2nd) on your bike is still present, lower than it is in 5th gear then I think you have found the answer. If it is not present at all, then it could be rims and or tires, and possibly the shaft drive system consisting of the shaft assembly with the universal gear on the output side of the engine. I would suspect things are not tight with the shaft itself, and the shaft itself vibrate up and down along the axis of the bike.
Like I said earlier, I am surprised more riders are not reporting this problem. I would be interested to know what you find when you run this test yourself.
Rhody
Kirrilian
Well-known member
rhody, that is a great suggestion, and that way I dont have to violate any speed laws to check it either LOL
Sorry I havent been on this thread in awhile, busy with work and play. I'm sure yall know how that goes.
Sorry I havent been on this thread in awhile, busy with work and play. I'm sure yall know how that goes.
Kirrilian
Well-known member
From what I gathered from this thread and the other one these folks have experienced the same issue (or something similar)
SPORT
rbentnail
rhody
fraler
mikep
Anyone else?
SPORT
rbentnail
rhody
fraler
mikep
Anyone else?
Kirrilian
Well-known member
Ok did some more testing today on the "track" (wink, wink)
It does NOT do it at the same engine RPM (bout 6k on my bike) at lower speeds. I tried 4th, 3rd, and 2nd speeds
It does NOT do it if I go above 120 and pull in the clutch and let the bike slow down do the speed where it happens
It does do it from 110 to 120 while the engine is engaged and it increases as the speed increases
I am thinking it is in the drive line like the drive shaft or bearings.
Any one else have any suggestions?
It does NOT do it at the same engine RPM (bout 6k on my bike) at lower speeds. I tried 4th, 3rd, and 2nd speeds
It does NOT do it if I go above 120 and pull in the clutch and let the bike slow down do the speed where it happens
It does do it from 110 to 120 while the engine is engaged and it increases as the speed increases
I am thinking it is in the drive line like the drive shaft or bearings.
Any one else have any suggestions?
rhody
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Trying to save a dying thread....
Clicky
OK SPORT, rbentnail, frailer, mikep, Kirrilian,
Fast forward this video to 2:04 - 2:08 and watch a few times, this is a 2009 Yamaha VMAX shaft drive visualization, ,with each component, displayed
in semi-slow motion in a slow rotating 360% view. all the universal joints and gears are displayed in detail, any theories about how all of these spinning whirling elements precisely at 110 mph on Gen II FJRs could result in vibration experienced by all listed above.
I am interested in your ideas, now that you all have something to visualize, refer to and play back endlessly....
If the source of the thumping starts here, I am all ears....
Not trying to be funny... just trying to contribute to solving the puzzle.
Could it be the shaft drive? Perhaps. It's been awhile since I've felt it, investigated or persued the reasons for that vibe. I've since re-shoed it and now winter has set in, so my riding is much more tamed. I'll re open this case in the spring/summer and see if i can't find more support for your theories.
Thanks for keeping me in the loop.
Sport
Thanks for keeping me in the loop.
Sport
I didn't get a chance to take the bike out for a good run before the snow came to try out rhody's theory. The first
time I can remember the thumping was on my first trip with the bike returning from the IBA national meet in Denver August of 06.
Once I got home I forgot about it till the next time I got well into the triple digits. Anyways, the bike was brand new at that time
and I've had the driveshaft and rear end apart several times since then to clean and lube the splines and looking for an obvious
cause for the thumping.
I really don't think it has anything to do with just engine RPM because I would have noticed something by now. (but i've been wrong before)
I think it is coming from the drive line, just not sure where.
Come spring I am going to buy a new U joint and give that a try.
Merry Christmas to everyone
Frank Heizler
time I can remember the thumping was on my first trip with the bike returning from the IBA national meet in Denver August of 06.
Once I got home I forgot about it till the next time I got well into the triple digits. Anyways, the bike was brand new at that time
and I've had the driveshaft and rear end apart several times since then to clean and lube the splines and looking for an obvious
cause for the thumping.
I really don't think it has anything to do with just engine RPM because I would have noticed something by now. (but i've been wrong before)
I think it is coming from the drive line, just not sure where.
Come spring I am going to buy a new U joint and give that a try.
Merry Christmas to everyone
Frank Heizler
Kirrilian
Well-known member
I am downloading the video so I can slow it down and watch it in detail. There were some things that interested me while it zipped past like that final u-joint for example.
Kirrilian
Well-known member
I am curious what RPM those gears and shaft are going at the same speed we feel that thumping. I'm not sure my math skills are up to it anymore but I will give it a go but I will need the specs for those gears. The reason why I want to know the RPM of the driveline is that the thumping isn't anywhere near the engine or tire RPMs. I would say for my bike it is about 2-3 thumps per second or about 120-150 per minute. It does increase in speed if I go faster but not much, thats why I didn't notice it before since the increase in frequency of the thumps isn't that much. I would agree with Frank, the u-joints are certainly suspect and I have had similar problems on my cagers before, anyway I am still riding but I don't get too crazy in the winter it is already too dangerous and cold!
Glen
Glen
Kirrilian
Well-known member
A thought just struck me, what if the driveshaft was just a tiny bit off true and something was hitting the axle housing but only at those speeds. In other words, at lower speeds the centripetal forces aren't enough to make whatever is hitting hit but as soon as you get to a certain speed it starts. Or maybe it is some sort of resonate vibration causing it once it gets to a certain frequency but it feels more like something is making contact with something else, the thumping is pretty significant on my bike not just a vibration. Anyway, some more ideas to throw out there, I think next spring/summer I am going to take the drive line apart and check all the parts for trueness or play in the u-joints or something.
OGRE
Well-known member
Haven't taken the time to read this thread until now.... My 06 also has a "thumping" at 100+ I only feel it under heavy throttle. If I reduce throttle the thumpiung reduces in intensity in direct relation to reduction of throttle and finally goes away. Pulling in the clutch stops the thumping immediatly. It only occurs in 5th gear.
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