Why does TBS help with engine vibs?

[Auron]

Would checking the torque of the 2 common (frame slider bolts )ones first cause any problems? Should I loosen and re-torque or just see if they are tight?

Loosen and re-torque in the proper sequence.

The link is helpful but has someone made a proper list?

 

[bluesdog]

Would checking the torque of the 2 common (frame slider bolts )ones first cause any problems? Should I loosen and re-torque or just see if they are tight?

Loosen and re-torque in the proper sequence.

And loosen in the proper sequence too right?

I believe loosening both of them, in what ever order you happen to do so is OK. When both are loosened,torque the left first, then torque the right

 

[RadioHowie]

Would checking the torque of the 2 common (frame slider bolts )ones first cause any problems? Should I loosen and re-torque or just see if they are tight?

Loosen and re-torque in the proper sequence.

The link is helpful but has someone made a proper list?

Easy-peasy...

Torque the two left main-spar bolts FIRST...then, loosen the pinch bolts on the right main-spar, torque the two right main-spar bolts, torque the pinch bolts. DONE!

Don't worry about the other 5 motor mounts. It's the 4 BIG ones that matter.

 

[wheatonFJR]

Easy-peasy...

Torque the two left main-spar bolts FIRST...then, loosen the pinch bolts on the right main-spar, torque the two right main-spar bolts, torque the pinch bolts. DONE!

Don't worry about the other 5 motor mounts. It's the 4 BIG ones that matter.

Good thing the OP has you for a guardian angel Howie. First the top case bracket subframe...now this.

 

[Auron]

Indeed. Thanks to everyone for answering all my noob questions. I'm having some anxiety over the vib issue, I just want my new bike to work like I envisioned it to. I'm planning to do some serious riding (aren't we all) on this thing and the sooner I can get it sorted out the happier I'll be.

 

[RadioHowie]

Good thing the OP has you for a guardian angel Howie. First the top case bracket subframe...now this.

Cashin' in some "Karma" checks.

The Forum has helped me SO much, I'm tryin' to give back the only way I can.

Notice I haven't lambasted poor, old Auron for buyin' a POS Gen II?

 

[majicmaker]

Good thing the OP has you for a guardian angel Howie. First the top case bracket subframe...now this.

Cashin' in some "Karma" checks.

The Forum has helped me SO much, I'm tryin' to give back the only way I can.

Notice I haven't lambasted poor, old Auron for buyin' a POS Gen II?

Karma only works when Karma is Deserved my Friend. You're Howie! Nuff Said. But, giving back is Always a Good Thing.

 

[Slardy]

Auron,

I have had 2 FJRs and I have experienced RPM related vibration to varying degrees with both of them.

Why do I say varying? Because after I installed a new triple clamp and torqued the steering head according to the book, the vibration level was reduced significantly. I suggest that you retorque the steering head (buy a new rubber gasket-yes rubber although it looks like it should be metal in the microfische), and fork tubes.

Hope this is of help.

Slardy

 

[Auron]

Thank you Slardy. Can you point out gasket in the link?

https://www.ronayers.com/Fiche/TypeID/26/Type/STEERING/MakeID/4/Make/Yamaha/YearID/45/Year/2004/ModelID/6048/Model/FJR1300/GroupID/244373/Group/STEERING

 

[Redfish Hunter]

I'm screwed. I'd say it's all in my head but after riding a silky smooth ST1300, I just don't see how anyone could ride a FJR (my FJR at least) at sustained speeds of 85+ without going nuts from the vibration.

I think it's all in your head. I own an '04 ST1300 and silky smooth it is not. The suspension is softer, the brakes, the throttle, the clutch are all smoother and softer but the engine is NOT smoother as far as vibration. It's vibration does manifest itself at a different point in the rpm range, but it is definitely there. I will concede that the Honda is probably smoother in the 70-85 mph range.

I rode a BMW R1200RT recently and it vibrated worse than either the FJR or the ST1300. And it was quite pleasant. I would not consider it bothersome at all.

The Honda V-4 fires two cylinders at a time making this thing fire like a V-twin (the lumpy part) It has two gear driven counterbalencers(the whiny part) It's vibration is there, is more pronounced but is on a very different frequency and feels different from the FJR.

I have been riding Dad's '07 FJR for the past few days and in fact rode the two bikes back to back yesterday. They both have some vibration but neither one is particularly bothersome. If you are going to ride a 1300 cc sport tourer, you want there to be a motor in there somewhere. At least I do.

 

[Fred W]

I may have more experience with doing throttle body synchronization than anyone else on this forum.

Why? Because when I got my bike it vibrated excessively in certain rpm ranges as you say your does. And when I did get a vacuum balance tool and started playing with it, I found that I could effect where (rpm range) the buzziness occurs at. And then I started experimenting with a bunch of different ways to get it perfect. But not just by adjusting the silly air screws, as shown in the Factory Service procedure. That procedure is pretty much a waste of time. All it does is balance the vacuum at idle, with an increasingly diminished effect as the throttle is opened.

The Really Defintely Completely Unauthorized TBS procedure that Howie linked you to previously, is what I came up with that actually makes a difference. Even on bikes where the owner was previously satisfied with the amount of vibration, a noticeable improvement can be made. People that say a TBS doesn't do anything are not talking about this RDCUA TBS procedure, they are talking about adjusting the air screws, and I agree with them on that.

At NERDS tech day this year we did the RDCUA TBS on 5 or 6 bikes, of mixed generations. In every case the riders came back and told me that the vibrations were reduced in the cruising rpm ranges. How much of this was placebo effect is always uncertain, and how much actual difference there was would depend on how out of balance the TBS was to begin with. Most of them were pretty significantly out. But I can tell you that when I was first developing the procedure I was being hyper-critical of it, as I didn't want to tell people to go through something that would negatively effect their bikes. The improvement in vibration was very real and completely tangible.

Will the vibration go away in all rpm ranges? No!!

What ends up happening is that you will get the balance nearly perfect in one rpm range. When you are riding along you will notice a "sweet spot" where the vibration is completely gone. Ideally on a 2nd gen you want to shoot for that perfect smoothness near 4k rpm because that is such a useful rpm for cruising. In my last adjustment I somehow got the balance perfect at ~5k rpm with a little buzz left at ~4k and it starts to comes back a little at ~6k. This is a good compromise on a 1st gen with shorter gearing as 5k in top gear is 80-85 mph. There is actually more vibration on my bike right now at 70-75 mph than at 80-85 mph which is kind of cool (so long as the RD is working).

I would recommend that you read through that procedure closely and give it a try yourself. It is not all that difficult to do.

At various times I have also felt a need to re-torque the engine mounts, as previously mentioned. The way that I knew that was the problem was that the vibration would come and go at a steady rpm as you weighted and unweighted the suspension, riding over irregularities in the road. The engine is a stressed part of the frame system on and FJR, and with the alloy frame (which happens to get very hot BTW) there may be some minor dimensional changes that occur as it heats.

One thing that is worth adding to the torque procedure is to torque those engine bolts after you have run the bike hard for a while. Get the frame good and hot, then bring it back to the garage and go through the 4 bolt sequence. This will work better to get the engine in that happy position in the frame at operating temps.

But... I could also be completely wrong... Right Skooter?

 

[Auron]

^ Great info there.

If I could move that buzz from 4K to 5 or 6K I'd be in heaven with this bike. I'll be doing it this weekend and hopefully be able to post postive results.

 

[SkooterG]

But... I could also be completely wrong... Right Skooter?

Glad you said it so I didn't have to!

I still think you are some snot-nosed 13 year old pimply-faced kid with the gift of gab. And apparently also with wealthy parents that allows you to hire out a 'stunt doulbe' if you will, to go to these various FJR gatherings to perpetuate the Fred W myth. Though ya think you could have picked a better looking example to represent your online persona.

So when are you going to get this ugly example of Fred W to actually ride out west for a change so he can screw up my FJR with this *smoke & mirrors* procedure?

 

[Fred W]

I'll have to check with my Mom first... :blink:

But... what's keeping you from all the East coast affairs?

That was a rhetorical question. I already know the answer. It's Kansas, Nebraska, Missouri, Indiana, etc.

Oh geezus. That kind of a post gets you a + vote? What is this forum coming to?

 

[Slardy]

AURON,

The 2004 fische that you referred to and the 2007 fische that I looked at both show item # 90202-30235-00. It is rubber and is called a WASHER PLATE!

Slardy

 

[Constant Mesh]

A sidenote to this discussion is the effect of the flow orifices on the column heights. I use the four column mercury balancer with flow orifices in each hose. Each column, hose, and orifice is supposedly identical. Yet, when I tee them all together and connect to one of the TB ports the column heights aren't equal -- there is variation between columns, not a lot but it's there and it's repeatable.

For a wheeze I balanced all the TB's with just one of the mercury columns. The small differences in hoses and orifices were removed from the equation. The final result was a bit different and could be easily detected.

An ideal setup would be to use one column that you could easily switch back and forth to all 4 TB's during continuous engine operation. Remove the variation in column components from the equation.

 

[Auron]

Alright, are you guys ready for the verdict???

Here's how I rate engine smoothness at 75mph in top gear for a few multicylinder bikes I've put at least 500 miles on.

0 = smoothest

10 = buziest

02' Goldwing 0

03' ST1300 2

02' Blackbird 4

06' R1200RT 4

01' 929 9

99' Bandit 1200 8

09' My FJR1300 8

(before tbs)

I was very, very unhappy with that 8 my new FJR was scoring. I broke the golden rule and changed several things at once but whatever it's not like I'm racing or anything. We found the throttle bodies to be quite a bit out of sync, my Dad was amazed to find only 1/10th of a turn on the linkages leveled them out. We got them as even as we could at 3,4 and 5K, while focusing on 4K. I just took the bike out and I'm very happy to say it's now a...

3!!! :yahoo:

The surging is gone too. I give the vibranators I put on a 6/10 because the bars now have zero vibration but I can tell they aren't the reason beause thee is a very very light buzz in the seat, tank and pegs. Money well spent though since a nice pair of bar weights are only $30 less.

So, for my money tbs DOES help vibration and very much if yours is as screwed up as mine was from the factory. It probably doesn't do much for those bikes that are good to begin with but mine was horrible but now it's all silky smooth so I can get on with loving my new bike.

Thanks everyone!!! :yahoo:

 

[Auron]

(Note: do NOT click the "play" button if you're squeamish)
https://www.youtube.com/watch?v=fm41UzssIvw

That's me on the left there

 

[Redfish Hunter]

I guess I have been guilty of the "Well MY bike doesn't do that so it must not really happen" syndrome. It is fairly common, not just here but on every forum I have ever seen. Dad's '07 has always been silky smooth at every speed above idle. Once I installed the PC-V it got smooth everywhere. Therefore I ASSUMED...

 

I am very glad you got your vibes taken care of. I hope you can now be happy with your FJR.

 

[Fred W]

Just remember... a TBS doesn't do anything. And enjoy your new bike.