Aluminum Bars, Vibrations, what to do

[KB2WYL]

Hi all. So over last couple of days I put some new bars on. Been wanting to do this forever. I like to shop local, and it just so happened local shop had these KTM bars. From what I can tell, same as the Renthals. Very little sweep, similar rise to stock. I had heard of aluminum bars being worse for vibes, but my bike NEVER gave me any problems with vibes. I did get some TERRIBLE problems from my carpal tunnel syndrome with the stock bars, and these bars are great for that. Seriously, I used to ride maybe 30 min (max, sometimes 10 min) before hands going numb from cts. These bars, I just rode 2 hours, no problems....But!!

The vibes are terrible now. I have to ride with no grip, hands barely touching. I know I know, this is how to ride...but not when I'm laying down on the tank trying to carve some corners it's not. It's definitely from engine, RPM related, but I didn't do anything other than change the bars, and with the stock ones I was feeling nothing in the bars.

I did not try to machine the bar ends back in to the new aluminum bars (I could, but it would be a pain). I thought about filling them with something (Epoxy? Lead?)

Has anyone else ever experienced this, gone from no vibes to holy crap vibes just from changing your handlebars?

Thanks guys...They look great and like I said, the cts relief, I'd REALLY like to keep them!

 

[FinalImpact]

I had some Renthal's on, didn't like the rise, they were aluminum and I didn't have bar end weights. They didn't seem any worse. For kicks, pop that brace off, it *should* reduce the harmonic frequency of the vibes. It could increase the "volume" so to speak, but reduce the oscillation frequency.....
Some fill them with lead shot and other items. I would not recommend silicone personally. To acidic, it will attack things!

Can you tap them to use oem bar ends? Maybe weld in an insert or toss a Helicoil in as a filler?
Tap an insert may cost more than bar ends??? Last idea, bark busters (aluminum braces).... changes the frequency again...

Last thought, some have had issues induced by the coil wires. It makes a wicked harmonic vibe just outside of 4k any speed. Look up a cure for vibrations, spark plug caps...

 

[KB2WYL]

Thanks Randy! For what it's worth, if I were describing this I would describe it as "I can feel the exhaust tone". I would 100% have blamed it on the new exhaust cans, had I not taken the few rides already with the stock bars, trouble free. Like a dummy I tested the new bars on a 2.5 hr trip I had to take today. It was cold, so lots of laying down. Every time I came out of a corner still in 6th gear and now down to 4-5K (I can do that now, thanks [MENTION=15974]FinalImpact[/MENTION]), it was like I was praising and cursing the trigger mod at the same time! That rumble I loved a few days ago, not fun today Blah

Yeah things I was going to do for sure were (In this order)

1.) Spark plugs caps (as I want to check them anyhow, in leu of a data logger, and who knows maybe one coming loose just happened at time of bar install). Also check rest of wiring/etc, buts this is usually more apparent at one spot. My vibes are even, every gear, every speed, from idle all the way up past where the engine naturally smooths out a little, past 6K.

2.) Bar ends. Some say yay, others nay, with aluminum bars. You're right with the stock weights and these bars. Time, and $$ to buy that huge tap I don't have. Plus, our stock ends are made to support 1/4 of our grip's end, and I already have these bars cut perfect length. Grips end at bar's end. But since I'm not going back to stock bars, what I CAN do, is grind down threads a bit and then re-tap with some big NPT (I do have those), and at least get them stuck in the ends to see if the "end weight" helps any.

3.) I think we have similar thought patterns Randy, ha! It came to my mind as well, Vibration shows up out of nowhere? Must have put something resonant on the bike....I looked it up and yep...l searched a lot of threads and seems the elders put it best, simply: Some bars aren't a good match for your bike. Bottom line is, if I think something might be resonant and causing problems, change it's size! And sure, I'm fine with about any amplitude as long as the frequency is low enough.


Real quick, not to get off thread, when I do the sync I have a 4 reservoir fluid sync. You know the type, hook up a source so that it pulls on all 4 at same time, set the set screws so that they're all at the same level, ok now you're ready to hook all 4 up individually to your TBs.

Each time I do the sync I always wonder about this....if you get them sync'd at idle, then hold at let's say 4k, now they're all way off from one another. Sync them while you're holding at 4k, and when you let back down to idle they're all way off. Now I know you're supposed to sync at idle, rev few times, make sure, etc etc....but if when you're revving it up they are all at different spots, how in the heck is it helping you any with smoothing out vibrations in the real world riding, where we are rarely at idle?


Loren

 

[KB2WYL]

Alright, before anyone responds, some more info. I hope it's okay to post these pics here. Now that I see these, I really think it has something to do with the vibration, so it is relevant to the thread big time. Most likely it was there, I'm just feeling it now with the Aluminum bars. It's teaching me that just because "Bad Vibes" aren't bothering me, doesn't mean I shouldn't be watching out for them.

So, pulled the radiator and the boots tonight. All boots were fine, #1 took about a turn to tighten all the way, rest half or less, no wiggle. Good. Then, pulled the plugs.

Here's #1. The orange is from an octane booster I rarely add. Today just happened to be a day I did, riding through steep mountain passes. Otherwise condition of plug looks OK, but not good. Center insulator has some cracking. These are CR9EIX with about 6K miles on them??

Here's #2. This one worried me a little. Seems to have the same orange deposit from the booster, but also a bit darker. And, it was the only one that came out a little moist. Did it just happen to get the last of the unburned gas shot on it when I shut the bike down (about 5 hours ago)? That's my thought, and I hope so. Didn't smell like oil, and my oil stays very clean. 300 miles since change (almost 400) and it's still looking brand new...

Here's number 3, and i won't even show #4. 1,3, and 4 all looked the same. Varying degrees of hairline fracture of center insulator, the orange deposit, luckily no physical damage to electrode or ground on any of them. You can wipe the orange off by finger only, and make them look like any other half good junkbox sparkplug. Wasn't until I was taking 30 minutes (darned phone) to take these pics that I even noticed the hairline CI cracks.


So, what it seems like to me is:

a.) get that fuel replaced, don't use that particular booster anymore, probably just don't use it at all, I mean 91 works fine anyhow.
b.) Add a little more fuel to the mixture, because minus the orange deposits, these things are looking pretty hot and lean
c.) Get colder plugs, I needed to do that anyhow after the trigger
d.) Those cracks might be hairline, but especially with that tiny iridium electrode, I must be getting some crappy spark

Seem right to you guys? Bet that would help, you know, engine running efficiently and all...Like I said I bet it was going on already and then I accelerated it by doing the trigger. I rarely go past 12K RPM, but then again I rarely go below 6K...I ride pretty aggressively. All that on the plugs to start with, then I do the trigger...and today she saw a lot of low RPM as well, as it was raining in the mountains on my 2.5hr trip...All combines to make for a great opportunity for just enough misfire that I don't notice it in particular, but it shows up in Bad Vibes

Loren

 

[TownsendsFJR1300]

Plus 1 on loose that additive.. Unless your having engine knocking/detonation, you don't need it. Even if you did, 91 Octane should solve that.

I've NEVER seen orange plugs. those plugs make me a bit nervous about what's happening inside that engine...

**BTW, OEM plugs, IME last longer than Iridums, stick with NGK's

Re syncing. I sync at both 4K and idle. Your should be able to get them very close at 4 (well with 10mm), then re-syn at idle. Your should easily be able to get them within spec's both at idle and 4k. If their still way off, you may need to check your valves or pull the filter and check the hoses going to the TB's. One member had a hose to the TB crack/split causing issues..

Re the bars, they make the handle bar Snake ( Barsnake ) that should help a bunch. It goes inside the bar.

I have "Grip Puppies" over my stock grips. Once you get used to the slightly thicker grip, IMO, their REALLY comfortable and DO help get rid of the minor vibs inherent in our bikes...


With your engine / exhaust mods, get the new plugs in there, loose the fuel with the orange crap in them and MOST importantly, CHECK THE COLOR / how their burning. The one pic has a bunch of "build up" on the ground electrode.

 

[KB2WYL]

Thanks Scott. The orange, I googled the spark plug charts (technology, just easier than grabbing the Haynes) and saw a ton of examples. A chemical in the booster, MMT, is responsible. MMT, or methylcyclopentadienyl manganese tricarbonyl is an anti-knock additive. Turns out that the brand I used yesterday, Lucas (and I like their other products, bummer) was high in content.

Yeah im going to try the stock NGK, just one colder. Maybe another brand even, not happy with that insulator crack, no excuse/reason for that in 6K

I will check out bar snake if I can't get it otherwise, thank you.

i couldn't imagine it has a leaky hose...:I've often wondered if my meters aren't to blame. Next time, just building one. I'll grab some tubing today.

Thanks again

 

[FinalImpact]

Curious now. What was your safety check regarding the trigger mod and how much the rotor was advanced???

IIRC if the rotors outer circumference rotates more than 0.110" you're upwards of +++7° of additional advance from stock. And depend on the load, that could be detonation that cracked those insulators....

The 650 ski I used to race (2 stroke) dropped a chunk of insulator and hosed up the piston, ring and cylinder. Ceramic is tougher than all those materials.
** do not put those plugs back in there!!! **

Hard to get a read there, but you need to know what caused those fractures.... at 13k its so busy there is no eay to hear detonation. Not that it only happens there could be way lower based on the map.

New plugs, proper gap. Best fuel you can afford and then get a read. See what the vibes are all about then...

 

[KB2WYL]

Exactly....Ok So safety check was pretty simple, long as you're paying attention to what you're doing (seemed to me at least?). Hash mark on the case, right angle to rotor, file, check, file, check, ok.

See I would have thought that I would have felt the detonation, or at the least felt a difference in "the way she was running" when I did it. But remember, I posted about the results, feeling not much difference low or high, mostly in middle, and nothing adverse.

Although again, maybe difference was there, AL bars just brought it to my hands.

But also, riding yesterday, it was not load dependent (happened same in straight as on hill climbs, exactly the same), AND seemed smoother past 6K. I would have ridden the whole ride like that, past 6K, but it was raining and I had my 13yr old son as passenger, so we were going for smooth ride not smooth on my hands.

Also, with Detonation, usually there is some damage to ground and or electrode, right? None here, nothing made it's way into combustion chamber (thank god, and hell no those plugs aren't going back in ;-)

My experience with small engines (don't know how much this applies with our 14K redline motors) is that deposits can come and go as per how the motor is currently running, what fuel you are using, plugged air filter, etc. But if you have deposits that are baked on, it's been going on for a while. With the orange wiped off, these plugs look like they are supposed to, except for those damn hairline cracks.

I just checked tracking on the Rotor, it should be here (the stock one, not the R one). So I'm going to go pick it up. When I get back I'll try to get some better pics of those plugs, so you can see.

For the Manometer, do you guys just use a leveling type, or do you go for level AND a specific Vacuum? It wouldn't cost much to build one either way, and this go around I am not using the plastic one again. Something about having to set the levels of all 4 of the fluid thermometers each time I use it just doesn't sit right with me. Like Scott said, I should be able to get it even at idle AND 4k. The fact that I can get it even at either one, and it STAYS even, leads me to believe it is a problem with my meter, like when I set the set screws I am making the meters all show the same thing, but only for the specific vacuum I am using for calibration. If I set it using idle, then when I try to check at 4k, I believe it is my meter that makes the levels get whacky.

See what I mean about the set screws?

 

[KB2WYL]

And just to get it cleared up and out of the way, i pulled the rotor and compared it with new one. It's pretty easy to compare, since I filled out the nub on the original, it fits snuggly into the recess for the nub on the new one. Put them both on a tight fitting shaft, and do comparative measurement.

From outside of my modified rotor, to outside of new rotor (outside to outside of one of the humps) .217"
Width of the hump itself (at the top of the hump, the part that matters as it is what passes under the pickup) .174"

Equals .043"

Which is within a couple thousandths of what I got measuring the other ways. So, maybe it's exactly 4.7, maybe more like 4.5, but certainly not over 6.

Randy, what happened with yours when you did go too far, what did you feel/notice? Or was the 6.0 and further = no good, deemed solely by the plug condition?

 

[TownsendsFJR1300]

Are the new plugs in, fuel replaced? That needs to be down before anything else (and then maybe the timing rotor)

Re the Sync, I have a Morgan Cartune ( Morgan Carbtune - carburetor synchronizer for balancing motorcycle carbs ) , no liquids.

As you can see, it has the #'s on the side (besides the levels), numerically, how close they are.

My last sync, at both idle and 4k was within 3mm (darn near dead on) both at idle and 4k (10mm is the spec limit)..
BTW, it's paid for itself several times over doing customers bikes (not even counting my own)


I don't know how your manometer is set up, but if that pic is accurate, the sync is off. How much, I dunno, should be pretty much even.
IE, if not the machine, part of your problem... I gather you did NOT adjust the CENTER, throttle shaft screw, correct?

**IMO, if I can't trust the accuracy of a CRITICAL tool, it's useless. Again, IMO, I'd but the Carbtune and take the guess work out of it...No liquids either to fuss over..

Lastly, try putting the stock bars back on and see if you still have the vibs (just for testing purposes). If you do, you know something new is happening and it's not the bars necessarily. If you have an accurate torque wrench, check the tightness of the engine mounts(specifically the RS "arm", (cold)).



Again, my last sync was within 3 mm's. The larger graduation is 10mm, so 3mm diff of the below pic...

 

[KB2WYL]

Thanks Scott. That pic is NOT hooked up to anything, just taken this morning for reference. Yeah, ha ha, that would be way off huh....

Yeah, I've thought about getting a good manometer. Thank you for that, I will check out and likely go with it. I agree, for precision....For now though, going to make one, as it was 5$ in parts, literally.

I know that if I make one, at least the levels will be the same.

I do not know about the one I have....I was wondering if any of you guys had ever tried one with the set screws like that?? I still don't see why you would have to set the levels on each, the whole point is that each one can affect the others the same way (as far as a simple fluid manometer)

And no, I did not adjust the center

Yeah, for testing it's going to be new plugs (CR10e) and fuel. Check and check, taken care of this morning (since it's raining and I can't work!). From there, we will see how it does with these aluminum "telling bars" once I feel the sync is closer. Also, I will try with and without the advance, since I now have both rotors...

Thanks again,

Loren

 

[TownsendsFJR1300]

I do not know about the one I have....I was wondering if any of you guys had ever tried one with the set screws like that?? I still don't see why you would have to set the levels on each, the whole point is that each one can affect the others the same way (as far as a simple fluid manometer)

And no, I did not adjust the center

Yeah, for testing it's going to be new plugs (CR10e) and fuel. Check and check, taken care of this morning (since it's raining and I can't work!). From there, we will see how it does with these aluminum "telling bars" once I feel the sync is closer. Also, I will try with and without the advance, since I now have both rotors...

Thanks again,

Loren

Ur welcome...10'S sound awful cold but just keep an eye on the plug colors..

I never heard of a set screw in a homemade manometer.

You do need a very SMALL restrictor in-line to keep pulses from jumping about.


I'd guess my restrictor might be the size of a sewing needle, maybe smaller...About 5" from the unit itself...


Interesting about the orange color with the additive too...

 

[KB2WYL]

No, The set screws aren't going to be on my homemade job. And yeah, thank you, I know about the restrictors, have a bunch of them in my parts drawers.

The set screws are on this motion pro "sync pro" of mine, the one I took the picture of with the levels off. The way it works is you hook a cylinder (any one, any vacuum source) up to a 5 way, one to vacuum and other 4 to the motion pro. Then you use the set screws to level off each reading, the thought apparently being that now each one shows the same thing for that given vacuum reading. Now when you go and hook up your 4 throttle bodies, if they're not all the same, the levels will be off. I think what it's for is being able to use it with high or low vacuum systems, so you can set the "scale" of the meter. But I'm not sure about how well that actually works out, when you're testing?

Loren

 

[TownsendsFJR1300]

Interesting, I've never heard of it

Here it is: https://www.motionpro.com/product/08-0411

From their site about the use: https://www.motionpro.com/motorcycl...tips_on_using_the_motion_pro_syncpro_08-0411/
Apparently, they get MANY calls from the experienced and non-experienced on how to use it.. No thank you...


IMO, I don't like it at all... Liquids to start with, (colored fluid available for sale).
*So you have to maintain it, hope you have enough fluid in it, or wait and buy some...

With the liquids, I don't know if it's possible to suck the fluid into the running machine by accident??

Now you have to adjust it with another vacuum to calibrate it? And if your off some, that screws up the sync...


For a simple, accurate sync, I don't want that, just more ways to screw it up...

KISS IMO...

 

[KB2WYL]

I'm on board with KISS. But, I don't have a problem with fluids. When I got that motion pro was years ago, and I didn't realize how bad it was. In fact, as I remember it was a "free gift" with a big order I made when I was restoring my 700SC. It did serve its purpos at the time, but now I want accurate. Homemade with fluids does offer accurate. If everything is connected with even lengths of tube, and the base of all 4 is even, it's simple physics. About as simple as one can get for testing vacuum. Shoo I think we've all seen the similar tricks using tubing for leveling. I still use that at work from time to time, if I have a need to be really precise and accurate over long distances . As far as sucking fluid into something, it could happen, but you'd have to be really careless. The vacuum reducers prevent sudden changes, and with a homemade the tubes are so long anyhow...

Regardless, yeah one like yours is better. No fluid, tells levels and compares levels. But, comparing the levels should be fine for what I'm after, for now. By the time I am pulling my plugs again, something like yours will be here, there are a few I've looked at.

as will a few different plugs, the rotor from the fz6r for comparison...right now I'm just seeing if I can indeed trace the vibration to imbalance in the throttle bodies. If so, yeah I'm sure to get it less and less as more precise testing comes into play when I do get different nanometers, and, when I do get the combustion more dialed.

thabks again Scott,

Loren

 

[KB2WYL]

Ha ha...you sent me down a rabbit hole, Scott. Suppose I could have looked this up before, but I was already set on the motion pro being something I wasn't going to use again, since the last time I sync'd the TBs, let alone this Vibe issue...

So, I had just been asking if anyone else had used it, or one like it, wondering what other's experience with them had been.

But now that I went and read that link, and took a closer look at the MP here, I see why it cannot work for idle AND 4k...and I suppose it's worth writing about, in case anyone else reads this and thinks they're going to get somewhere with their own motion pro meter...see if you follow me, or rather if I can make sense of it in writing...

The mp has 4 separate chambers. This may be like yours, and is similar to gauge units, which have 4 separate gauges. Works great if all 4 are accurate, even better if they're precise. But on the mp here's how it works:

Each chamber has fluid in it with a little air at the top. The fluid then goes out the back of the chamber, to it's meter. When you put suction on that meter and the fluid climbs up, you are reducing the pressure in the air space in it's chamber. The set screws change the volume of that air space. If I make the air space very small, then we need a lot of suction to get the fluid to move and reduce pressure in that small air space. If I back the set screw out and make the air space large, then less vacuum will get the fluid to move the same amount....

I drew it, as I'm pretty sure sometimes I try to hard to explain these things and I get confusing:

So, that's a great idea for their product. You aren't going to have enough vacuum during normal testing to get that fluid to come all the way up the meter and through the lines, because the air space being sealed behind it prevents that (with any vacuum we're talking about here). And, having the set screws is great, because just like I've been doing, you can feed any vacuum source to all 4 meters, and voila, now they all respond the same to that vacuum.

BUT....

The amount of air in each one is not the same. So, if I'm dealing with a low vacuum like at idle, and I calibrate them, then yes they all respond the same way to something very close to the vacuum I used to calibrate them. But if I increase that vacuum by more than double, like we are supposed to do at 4K RPM, then no they will not all respond the same way. The amount of fluid that moves up the meter, and the reduction in pressure in the remaining air space, is NOT a linear function.

A similar unit, that had precise amounts of fluid, and precise air pressures in the remaining spaces, would work great. But that's not what this is. This is budget.

I don't suppose it matters to get any more technical, but my point is, that this is what I already observed in using it. It works great, if you calibrate it at idle, OR at 4K RPM, but you can't test both instances with the same calibration.

The homemade job is so much simpler. Fluid fills 4 tubes. It's level is the same in each. Apply vacuum to 4 tubes and adjust until level again. You can apply as much vacuum as you want (as long as you're not collapsing the hoses) and the principle stays the exact same. Done. KISS.

Thanks again,


Loren

 

[TownsendsFJR1300]

Ok, I agree with most of what your stating. The change in volume, not being accurate at a different RPM, I don't buy..

The Carbtune, (as you know) uses solid cylinders and yes, all are separate from each other. I believe their completely
sealed so ONLY your engine vacuum is moving the cylinder(s).

I've never bothered with a homemade machine (I'm a tool-a-holic) however, I would trust a correctly constructed one over the MP (the more I learn about it).

*Re-reading your above post, I suppose, the weight of the cylinders themselves(in the Carbtune), work basically the same as adjusting the screws in the MP. Obviously the weight of the Carbtune cylinders don't change, need adjustment, etc, just WAY simpler...

I'd add, I've had my Carbtune since 3-17-2009, approx $82.00 shipped from Britain. Still looks like new and works as new, NEVER an issue. And there's no re-adjustment to check at 4K, just turn/hold the throttle.



.

 

[KB2WYL]

I agree with you on the Carbtune, found it on Ebay. Same price as on website. Around 100$ now, but still not a bad deal. Almost bought it last night, and probably will soon.

Maybe I'm wrong on the MP, but I don't think so ...

The Carbtune is far more precise. Not too hard to manufacture those metal cylinders all the same size/weight. So, differences in vacuum change each one's level more accurately.

Here's how I'm thinking of the motion pro.

I have to calibrate it because the amount of air (and therefore the amount of liquid, equal to the Carbtune's metal cylinders) is different in each meter.

lets say I put a small suction on one meter with a little air behind the fluid. I put the same small suction on another one of the meters that has more air behind the fluid. They both move about the same amount. But now lets say I increase that suction. Do I think both of the meters will move the same amount still, one of them being easier to move than the other (because it has more air behind it)?

This example wouldn't work with the Carbtune, as with the Carbtune the amount of air behind each of the cylinders is based on how much it's being compressed by the weight of the cylinder, which is the same for each cylinder.

I really don't get it with the motion pro, why it's different in each one. That's what kills it. The adjustment screws would just make a precision instrument more precise, if it had the exact same amount of fluid in each one. Whet I think is going on is that it is just not manufactured that well, so there are probably small differences in fluid, volume of the meter itself to start with from plastics manufacturing, how much pressure is created when the set screws are put in to begin with, etc.

Well, last night got the homemade one done. I'll take pics later, but it's sitting on the floor behind me, all levels exactly even.

It's sunny here right now, but supposed to be another 10 days of rain. Darn.

Thanks again Scott,

Loren

 

[TownsendsFJR1300]

I never really had issues with vibs in the stock bars. The "Grip Puppies" and my gel (inside the glove) eliminated all bar vibs.

I bought the Carbtune FOR the FZ as it developed a bad buzz that came mostly thru the right side of the seat (EXTREMELY annoying-almost sold the bike).

The sync was within spec, BUT fine tuning both at idle and 4K, getting them both within 3mm's (the shop wouldn't get them that close) solved the issue..

I did my research back then, liked what I read, and have done many a bike with it.

The FZ is buzzy to start with, but getting that sync as close as possible definitely helps..(BTW, I sold my FJR, Goldwing, and KLR250 and KEPT the FZ as it was/is my favorite bike and that buzz was eliminated...)


I ONLY sync when my right butt cheek starts getting "buzzed". Other than that, I don't touch em... It's probably been 2 years since I did them last..

 

[FinalImpact]

How about hook them ALL to one port so they all read the same signal and verify they all do the same thing at the same time.

And if you have a vacuum gauge, throw that in the mix as make shift calibration set point. Also, much past 3.5k and the air is going through the throttle body vs Idle Air Control Valve so vibes are caused by something other than TB sync....

This is not portraying any specific info but if you have a known good gauge, the idle speed and vacuum are telling you the AFR.... IIRC its roughly 12.5:1 at idle but I don't recall the vacuum value at 1300 that they wanted....