Bike wobbles in agressive turns

[naughtyG]

I think there's a little confusion by some on the problem discussed here:

1. Max handles GREAT for its weight and age in twisties AT LOWER SPEEDS up to 50/60 mph

2. The frame wobble happens ONLY in higher speeds turns, typically 70 mph and above. There the weight of the beast overpowers the frame and swingarm's abilities to keep things straight and smooth.

Of course better forks/springs and better shocks are going to help some, and better tires are always a plus.

But no matter what, at speeds of 70mph and up going over bumps is going to upset Max, and only frames braces or solid motor mounts and braced swing arm will help that. Fork braces are a waste of time, and suspension will only be of limited help.

No Max is never going to be an R1 or Fireblade, but it can be way more solid than it is as OEM, and definitely not as wobbly/scary in high speed turns.

 

[jfeagins]

What kind of rear tire do you have? Most have a cross sectional profile that has a "break" in it, a sudden transition of curvature. They are no good. You need one with an as round and smooth as possible profile. The wobble is initiated when you lean far enough to pass this "transition" point on the tire. I know. I experienced the same. Took me two years to finally attribute it to the tire and not to my lack of riding skill. I have an Avon Venom now, round as a balloon, now it corners beautifully. The left/right discrepancy is simply because everyone has a "favourite" side, one you feel more comfortable on, so unconsciously you`ll lean further that side so the problem will occur more frequently. Of course, all other measures mentioned here will help, but only improve, not solve. First things first: the tire. Cure the disease in stead of treating the symptoms.

Couldn't have said it better. I've been mentioning the rear tire for a number of years....it greatly affects the dreaded high speed wobble in a straight line too. But, unfortunately, seldom do I see anyone paying attention. They feel better spending lots of money on mods that assist in controlling the wobbles, rather than eliminating the need for assistance.

I'd say you're getting the frame wobble.(WTF? Frames don't wobble....they may flex a bit when circumstances permit it......but tires cause wobble) I had the same with my '86, and I had a beefed up fork brace, progressive springs and Intiminators up front, and Progressive 440 shocks on the rear, with the same tires you're running.

Your solutions/bandaides are:

1. Frames braces or solid motor mounts
2. Braced swing arm

SMM is the cheapest, you can get a set for around $50. Frame braces is the easiest - you just bolt them on. Swing arm is the most expensive I think, depending on whether you're buying it or doing it yourself..

I think there's a little confusion by some on the problem discussed here:

1. Max handles GREAT for its weight and age in twisties AT LOWER SPEEDS up to 50/60 mph

2. The frame wobble happens ONLY in higher speeds turns, typically 70 mph and above. There the weight of the beast overpowers the frame and swingarm's abilities to keep things straight and smooth.

Of course better forks/springs and better shocks are going to help some, and better tires are always a plus.

But no matter what, at speeds of 70mph and up going over bumps is going to upset Max, and only frames braces or solid motor mounts and braced swing arm will help that. Fork braces are a waste of time, and suspension will only be of limited help.

No Max is never going to be an R1 or Fireblade, but it can be way more solid than it is as OEM, and definitely not as wobbly/scary in high speed turns.

Again, frames don't create their own wobble, tires do. Loose bearings would/could cause a sudden jerking, or changing of direction based on bumps in the road, so it's always good to have good, properly adjusted bearing too, but tires wobble. Frames don't. PERIOD. (guess in an extreme case, it could also be a bad wheel).

I'll go back to my hidey hole now, and please people, DON'T ANYONE LISTEN TO ME. I'm used to it. :biglaugh:

 

[Sonoran6]

I've experienced the turn wobble at speeds much less than 70mph. More like from 40-60 depending on how tight it is. We got some crazy canyon twisties and switchbacks out here. No high speed wobble tho, I've gotten up to 140 a couple times. Just got a jiggling front tire, up and down vibration. Since I will need a back tire before my front needs replaces I will try a Venom rear. Wish they had an Avon Venom in OEM front size too.

 

[ouchez]

I've experienced the turn wobble at speeds much less than 70mph. More like from 40-60 depending on how tight it is. We got some crazy canyon twisties and switchbacks out here. No high speed wobble tho, I've gotten up to 140 a couple times. Just got a jiggling front tire, up and down vibration. Since I will need a back tire before my front needs replaces I will try a Venom rear. Wish they had an Avon Venom in OEM front size too.

I think I got the last front venom in existence, and it is one hell of a tire.

O

 

[adamax]

5 seconds test #1 : pass your palm over the front tire, if you feel hi n lo you spotted a problem.
5 seconds test # 2: stand behind the bike upright and observe the rear tire curvature, it it exhibits a flat surface at the center ( maybe 2" or more ) you spotted a problem.
I also read wheel bearings in a post, they are often a culprit.
I had a wobble only on turns and it was a front tire, and I had a wobble running straight on a another vmax, and it was the head bearing. I suggest do the preliminary inspection.
Again, all other mods will significantly improve the ride quality and take care of all sorts of wobbles and shakes.

 

[adamax]

5 seconds test #1 : pass your palm over the front tire, if you feel hi n lo you spotted a problem.
5 seconds test # 2: stand behind the bike upright and observe the rear tire curvature, it it exhibits a flat surface at the center ( maybe 2" or more ) you spotted a problem.
I also read wheel bearings in a post, they are often a culprit.
I had a wobble only on turns and it was a front tire, and I had a wobble running straight on a another vmax, and it was the head bearing. I suggest do the preliminary inspection.
Again, all other mods will significantly improve the ride quality and take care of all sorts of wobbles and shakes.

 

[dwarf717]

Sorry but no way :confused2: Considering the weight of the Max, it`s remarkably balanced, I can keep it upright with a single finger
They just put the wrong tires on it: perfect for straight-line, lots-a-grip, use all power you have to launch without spinning, dragging
But the right tire will make it handle just as well as any bike
To get it up to modern standards of course you can reduce flexing, improve suspension,...
But there aren`t many out there who can push the Max to its limits and have any ground for complaining :biglaugh:

The VMAX is an ass heavy bike, and my hoist will attest to that! I've had Hardleys on it, a KZ1300 6cyl. touring bikes, and Ventures. None of them I noticed anything different about when being lifted... My Max however, makes the hoist lean back pretty hard. As for tires, I have Pirellis. The bike does handle pretty good, but I do have to be mindful of any wallows, dips, or bumps in the corner as they will unsettle the bike pretty easily. I also have to be carefull, as I have a tendecy to ride the tires to the edge, and even have started to ride over them. Sliding a 625 + 200 lb me is not a very confidence inspiring thing to do on a Max. Used to do it on my VTR, but had a knee down when doing so, and really was no big deal doing so...but on a Max, it is a big deal.

 

[naughtyG]

Indeed, I've been scraping pegs on both sides on the Max with my cheap Shinko tires and have NEVER had a single wobble at lower speeds. Above 70mph, it's another story. Any irregularity in the road will send it wobbling all over the place, and there's nothing wrong with those tires (ok I'll admit that having a 90 profile rear on a 15" wheel doesn't help..). Still, it is the frame and swingarm that flex and create the wobble, which is why (lots of) people fits frame braces and brace their swing arms!

 

[Miles Long]

Seems to happen more when taking right turns and at first I chalked it up to me just being a new rider. After a recent trip through the Salt River Canyon here in AZ, I decided that it must be something related to my suspension. To describe the wobble is difficult, it isn't constant and has happened on different occasions with varying speeds and lean angles. I did take note that it is happening usually on right leans, but has rarely happened on left leans too. It starts off subtle then gets more violent until the bike is back upright. This is terrifying because it changes my line and has forced me into oncoming traffic lanes. Any help diagnosing and fixing this issue would be very appreciated.

Are you a "lightweight"? If so, get a buddy to help you check the preload of the shocks, with you sitting on your bike. A rule of thumb is that the shocks should be compressed 1/3 of their total travel, when the bike is loaded.
If you have lowered your front end, I believe this also has the effect of "unweighting" the back end a corresponding amount, so that existing preload may be lessened.
Improper preload could be a contributing factor to the wobbling during the turns, particularly if you encounter washboard asphalt .
Just something easy to check, won't cost you a dime.
Cheers!

 

[Sonoran6]

Are you a "lightweight"? If so, get a buddy to help you check the preload of the shocks, with you sitting on your bike. A rule of thumb is that the shocks should be compressed 1/3 of their total travel, when the bike is loaded.
If you have lowered your front end, I believe this also has the effect of "unweighting" the back end a corresponding amount, so that existing preload may be lessened.
Improper preload could be a contributing factor to the wobbling during the turns, particularly if you encounter washboard asphalt .
Just something easy to check, won't cost you a dime.
Cheers!

I weigh 135, with full gear I weigh 152. My preload is set at 1 on stock rear shocks now and the rear shock moves down about a half inch when I sit on it... Also I did the Salt River Canyon run again and made note of the turn wobble speed, it was around 70 mph both times it happened.

 

[Sonoran6]

Problem cured!!

Pirelli Sport Demon front and Pirelli Night Dragon rear. The sine wave groove in the front tire eliminates groove suction too, no more wobbles and no more getting sucked into highway grooves. Pirelli has a lifelong customer with me.

 

[Redbone]

I know the feeling. I equate it to trying to ride a dog that is wagging its tail. I only felt it when pushing hard thru turns. Progressive springs w/intiminators, 440's out back, and solid mounts made things better but that feeling was still there. It did not go away until I installed a braced arm, radials, and USD forks.

Seems to me the common factor is a braced swingarm which, makes sense to me because the feeling was coming from the back end of the bike. I think it would be interesting to hear from someone that has installed a braced arm and no other handling mods and see if that has taken care of the wagging feeling.

It sounds like what I was experiencing, at one time. It feels like things are shifting and flexing. It went away, after I installed solid motor mounts and a braced swingarm. I did them both at the same time, so I can't attribute the solution to one or the other. Although, it may have needed both to stiffen up the frame adequately.

Most of us don't need the Vmax to corner like a sportbike, we just want it to corner safely. It doesn't matter what bike it is, if it wallows and bucks in a long sweeping corner at or under the speed limit, there is an issue that needs to be addressed. My '88 had all new bearing (swingarm, head and wheels), rebuilt front suspension with progressive shocks, stock rear suspension in good condition and good tires properly inflated... and it still wallowed scarily.

My '92 by contrast, has a fork brace, frame brace, swingarm brace and solid motor mounts... and it corners with confidence. No more hinge under the seat feel... Just my :twocents:

I have a long corner with some small bumps and a couple areas that are slightly lower that feel like a roller coaster when doing 60 and under. The fastest I had been able to go through this corner was ~90 with the hinge effect stopping my good sense to go faster. I have fork braces, progressive spring, ricor intinminators, delrin motor mounts, hd 440 shocks on the back. These changes all made it better but the hinge feeling was still there. Last year I put on radials and a extended braced swingarm and I was able to go over 100 with ease, I was kinda surprised the first time I did it so I tried again, same result. I can now go through the corner at 120 mph and that is good enough for me. My brother on his FZ1 would go through the corner at 130- 140 (at least that's what he told me, I could never keep up to him on our lakeshore road) but my Vmax will never get to those speeds
I had a issue with my Shinko T230 front tire where I would get a 40-50 mph wobble while turning and that tire lasted only 3000 miles for me. I also didn't like the line down the middle of it especially while crossing the Mackinac bridge which has 2.5 miles of metal grating, not fun having your front tire dancing around in a 30 mph cross wind plus the 4 wind shadows that like to unsettle everything, especially the rider. I have yet to cross with my radials on but it has to be a lot better!

 

[DMAN999]

Problem cured!!

Pirelli Sport Demon front and Pirelli Night Dragon rear. The sine wave groove in the front tire eliminates groove suction too, no more wobbles and no more getting sucked into highway grooves. Pirelli has a lifelong customer with me.

Nice.
That's why I told you in another Thread that I always run a Sport Touring front tire (currently a bridgestone Batlaxx BT-45V) and the Stock size Shinko rear tire.
I ride a lot of twisties and the sport touring tires perform 1000x better than the cruiser style front tires for me.
And the wider rear tire (170/80-15) just didn't feel right to me in the twisties, it forced me to work harder than I like to take them at speed.
I run 70-80 through some pretty good back road twisties regularly without issues.

But Frames Braces and a braced swing arm would definitely stabilize your VMax even more in the tiwisties (neither of which I have btw).

PS
I tubed down the Salt River back in 1986 or so, it was blast.
They rented us a cooler and a radio built into inner tubes, you just have to love that.