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Help with vibration

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Hey guys, finally warm enough to start hitting some tracks here in new england. I am having big problems with vibration though on 06 125. I'm getting arm pump really bad, and I think the culprit is vibration through the bars. Last season I installed some bar inserts that seemed to help, but not enough. Has anyone tried going over to a rubber mounted triple clamp? I think it'll help but I dont want to shell out the cash for something that wont work. This is the one I was thinking of.

http://cgi.ebay.com/ebaymotors/Pro-Taper-COMPLETE-TRIPLE-CLAMP-Yamaha-YZ-125-06-07-/380334448596?pt=Motorcycles_Parts_Accessories&hash=item588db31fd4

or maybe even an older model like this

http://cgi.ebay.com/ebaymotors/Yamaha-YZ125-250f-06-07-PRO-TAPER-COMPLETE-TRIPLE-CLAMP-/150581028983?pt=Motorcycles_Parts_Accessories&hash=item230f542877

thanks guys :thumbsup:

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A few things could help you, just have to decide the order and what's a good fit.

- The mounts you listed above

- Flex bars Flex bar writeup

- Pro Taper pillow grips

- Make your clutch and brake levers as easy to pull as possible

so that you don't have to use much force

- Train your forearms with rotating and gripping exercises

- Drink lots of water, dehydration accelerates arm pump

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And something too simple: Are all of the engine mount bolts properly tightened? Lost motion makes vibration worse.

Sillier things have happened.....

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The rubber mount clamps help some, but I doubt it is enough to fix things. Do whatever the guys above me said. In addition, make sure your gloves are not too tight. I do much better with something slightly loose vs slightly tight.

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The rubber mount clamps help some, but I doubt it is enough to fix things. Do whatever the guys above me said. In addition, make sure your gloves are not too tight. I do much better with something slightly loose vs slightly tight.

Second on the gloves. If yours are leather, get them wet and wear them until dry on a nice day doing yardwork. It makes them the right size.

I haven't had a small bore two stroke in a while, but I kind of find it amazing it would vibrate that much. Big bore singles and four cylinders make my hands numb, but the smaller bores, and generally all two strokes, don't get me like the four stroke singles and rev happy fours. Have you compared your vibration to similar models owned by others? I find when my FI bikes lean themselves out in hot weather, that the vibration and power delivery have a very "coarse" feel to it, for lack of a better way to put it. I think this is because the FI overdoes it and I'm at the lean end of the scale.

Is your jetting and timing correct? I see from the parts list that it has a head steady, is that tight on both ends? Since the swingarm rotates though the cases, is there something sloppy there?

If it vibrates as bad as everyone else's, I guess you're stuck, unless you want to completely disassemble and have a professional balance shop redo it. I had this done years ago for an open class two stroke, what a difference. It also had more power, as it wasn't fighting itself. Lucky for me, I had it done for free, I would expect it to be pricey.

But: I suggest a quicker fix, which may be enough: Because I'm an old goat, I find vibration really really gets to me. My shop parts/accessory guy recommended ProGrip 714 dual sport grips to me. I tried a set, and now all of my bikes wear them. Got the tingle down to manageable level. Plus, they are somewhat barrel shaped, rather than a cylinder, which to me is far more comfortable. Try a set. Cheap experiment at 10 bucks or so. Let me know if it worked as well for you as for me. I won't use anything else.

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I'd bet it's not mainly mechanical. A 125 with a straight crank doesn't vibe that much.

Try to force yourself to loosen your grip and hold on with your legs more. Do you sit a lot? If so stand up and use your legs and core more. Warming up first helps too. If you're practicing only start off easy then ramp it up slowly. Beginning of the season will make things worse as well.

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yeah heres the story. went from a 450 back to a 125 last season for the fun factor. I will admit I am not in the best shape yet and the track yesterday was really rough. What are teh workouts to condition my arms? I've always have tried pushing too hard too early too, I'm used to it from racing. The problems I have are the arm pump and also my hands like lockup on the bars. I was a little suspicious of the solid mount bar system that yamaha uses because with the honda rubber mounts I never had these issues, even with the heavy weight of the 450

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yeah heres the story. went from a 450 back to a 125 last season for the fun factor. I will admit I am not in the best shape yet and the track yesterday was really rough. What are teh workouts to condition my arms? I've always have tried pushing too hard too early too, I'm used to it from racing. The problems I have are the arm pump and also my hands like lockup on the bars. I was a little suspicious of the solid mount bar system that yamaha uses because with the honda rubber mounts I never had these issues, even with the heavy weight of the 450

Sounds like you need to loosen your grip and use some softer grips such as pillowtops. I prefer a firmer grip and have no issues with the stock yamaha set up, no inserts or anything with Pro Taper Evo Windham bend. If you can get one of those spring loaded resistance hand grips to work with while your sitting at work, in class or whatever. Something like this http://www.amazon.com/dp/B0007W2FJ0/ref=asc_df_B0007W2FJ01526863?smid=ATVPDKIKX0DER&tag=shopzilla_rev_34-20&linkCode=asn&creative=395093&creativeASIN=B0007W2FJ0 The most important thing Ive found that works is to drink tons of water and stretch thoroughly before riding (this applies to all areas of the body) as well as making sure proper form and body position are used, being too far back on the seat and having your elbows down seems to speed up the process due to holding on with your hands instead of letting your legs do the work. Make sure your bars arent rotated too far back or forward or it will put your wrists in an odd position putting a little extra stress on your forearms, if you find yourself rotating bars too far you may want to consider some sort of offset setup. Last thing Ive found that seems to work is, I tought myself to keep at least one finger if not two on the clutch and front brake at all times, which makes me force myself to grip the bars that hard which only happens in the really rough stuff because I have to take that finger off the levers. After I felt I didnt need to keep that finger on the lever anymore I took the finger off the brake lever and havnt had any issues with arm pump since unless I stay on the track for over 30-40 mins at a time no matter how chewed up it is. Hopefully some of this helps.

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