Front end/fork/brake shimmy on 95 VFR

bcolins · 03-13-2007, 12:07 AM

Hi,

I'm new to this forum,....I came upon an immaculate 95 VFR about 4 months ago.........had to buy it.

I've noticed that I get a lot of front end shake that feels like a warped brake rotor upon hard braking.

The bike has had two previous owners.....the guy I bought it from said he never noticed any front end vibration on braking......and I believe him....having met him,......I doubt he ever rode it very far or very fast or used the front brakes very aggressively.

I have previously been told that it is nearly impossible to warp a bike front rotor since they are generally are a floating rotor.........but frankly dont know if that is true or total BS.

I have read previously that front end shaking on older VFRs is not an uncommon thing.....................

Any one have any ideas on what to check or how to fix this.?

Brian in Austin

viperpilot · 03-28-2007, 2:24 PM

Check the front tire for cupping. Replacing the cupped front tire on my '94 cured this issue.

gt702 · 03-29-2007, 11:48 AM

Quote:

Originally Posted by bcolins

I have previously been told that it is nearly impossible to warp a bike front rotor since they are generally are a floating rotor.........but frankly dont know if that is true or total BS.

I have read previously that front end shaking on older VFRs is not an uncommon thing.....................

Hi Brian, welcome to the group and congratulations on the VFR, they are great bikes.

While the VFR rotors are thick enough that they don't warp very often, they can be bent during tire changes or if something falls on them. Check this out by elevating the front wheel (can have someone push down on the back while on a center stand) and use a wood pointer (so it doesn't scratch) or something to hold against the fork and pointing at the rotor face, while rotating the wheel and see if there is any run out on the rotors. A little bit is OK, but any big changes can be an issue. The better way is to use a dial indicator, but the stick method works good for a quick check.

Check for cupped tires as noted. The VFR has a tendency to cup the tires. Well adjusted steering head bearings and adequate tire pressure (I usually run 38psi, +1-2 from recommended ... old Dunlops would cup at 36psi, but not at 38 ... go figure) in the front to minimize this.

And check the steering head bearings. Too much slop will let forks rock some in the bearings under braking which can cause a shudder.

I'm assuming the wheel is in alignment with the bars ... and make sure the chain is good, adjusted right, and has no kinked links. All of these could be factors.

And enjoy the bike. I'm on my second '94, having put over 80K miles on the 750's. My first bike is now at 90K miles and the friend I sold it to is still enjoying it immensely.

Gaunty42 · 04-04-2007, 10:46 AM

I had this on my 1996 VFR. I found that one of the pistons in the caliper was sticking so check that that too. Whilst we are on the subject of brakes you should consider changing the stock brakes with stainless steel or titanium brakes hoses. ( unless you already have them) I also added EBC uprated pads. My brakes are now a lot more powerful and smoother.

bcolins · 04-05-2007, 6:58 AM

Quote:

Originally Posted by Gaunty42

I had this on my 1996 VFR. I found that one of the pistons in the caliper was sticking so check that that too. Whilst we are on the subject of brakes you should consider changing the stock brakes with stainless steel or titanium brakes hoses. ( unless you already have them) I also added EBC uprated pads. My brakes are now a lot more powerful and smoother.

Thanks for the input. How do you determine if a piston is sticking?? What do you mean by your brakes being "smoother"

bcolins · 04-05-2007, 7:02 AM

Quote:

Originally Posted by gt702

Hi Brian, welcome to the group and congratulations on the VFR, they are great bikes.

While the VFR rotors are thick enough that they don't warp very often, they can be bent during tire changes or if something falls on them. Check this out by elevating the front wheel (can have someone push down on the back while on a center stand) and use a wood pointer (so it doesn't scratch) or something to hold against the fork and pointing at the rotor face, while rotating the wheel and see if there is any run out on the rotors. A little bit is OK, but any big changes can be an issue. The better way is to use a dial indicator, but the stick method works good for a quick check.

Check for cupped tires as noted. The VFR has a tendency to cup the tires. Well adjusted steering head bearings and adequate tire pressure (I usually run 38psi, +1-2 from recommended ... old Dunlops would cup at 36psi, but not at 38 ... go figure) in the front to minimize this.

And check the steering head bearings. Too much slop will let forks rock some in the bearings under braking which can cause a shudder.

I'm assuming the wheel is in alignment with the bars ... and make sure the chain is good, adjusted right, and has no kinked links. All of these could be factors.

And enjoy the bike. I'm on my second '94, having put over 80K miles on the 750's. My first bike is now at 90K miles and the friend I sold it to is still enjoying it immensely.

Ill try the stick trick. How do I check for steering head bearing tightness/looseness.........and is it something that I can adjust myself??

Gaunty42 · 04-05-2007, 7:14 AM

Quote:

Originally Posted by bcolins

Thanks for the input. How do you determine if a piston is sticking?? What do you mean by your brakes being "smoother"

You will need to remove your calipers. Then check each piston. I just removed them, cleaned everything out and re greased them. If the rubber seals are damaged you will need to replace them. With uprated hoses and pads, breaking is far more powerful and you don't need as much pressure and hence braking is smoother.

bcolins · 04-05-2007, 7:36 AM

Quote:

Originally Posted by Gaunty42

You will need to remove your calipers. Then check each piston. I just removed them, cleaned everything out and re greased them. If the rubber seals are damaged you will need to replace them. With uprated hoses and pads, breaking is far more powerful and you don't need as much pressure and hence braking is smoother.

Do I have to drain the hydraulic system to do this? Any suggestions on a good source for stainless brake line/s??

Thanks,
Brian

bcolins · 04-05-2007, 7:38 AM

Quote:

Originally Posted by bcolins

Do I have to drain the hydraulic system to do this? Any suggestions on a good source for stainless brake line/s??

Thanks,
Brian

Also,..........is standard wheel bearing grease the way to go,...or is there a grease specific to brake caliper pistons?

Brian

Gaunty42 · 04-05-2007, 7:59 AM

Quote:

Originally Posted by bcolins

Do I have to drain the hydraulic system to do this? Any suggestions on a good source for stainless brake line/s??

Thanks,
Brian

You do, but it's no big deal. Try www.perfectbrakes.com - online shopping for quality disc brake pads and brake rotors
for pads and hoses or GOODRIDGE GLOBAL | Home