Bike shakes when i brake

I just bought a used 2001 CBRF4i with 10000 miles on it.....( the guy wouldnt let me test drive it before i bought it)...so when i got home, the bike started, shifted fine, seemed like no bogging problems in the rpms. but when i brake the forks shake. I know it could be the rotors and or the forks leaking Gas? but i have 0 experinece with this. I dont want to go to a shop because i have 0 money at this moment. should i waste some money on some rotors rater than spend it on an anaylsis and then parts and labor...I have no clue. If you guys live around FSU let me know so i can learn anything about this bike

If you have a way to elevate the front wheel, try spinning it and inspecting the rotors. If you hear a dragging noise ( not just the pads on the rotor but a PRONOUNCED noise) you probally have warped/bent rotors.
The forks do not have "gas" they have oil, and if that was the problem there would be oil all over the lower fork or gunk collected on the slider.
Another problem could be your headset bearing could be loose or needing greased ( or both)

I didn't know the forks were gas charged. Sounds more like steering head bearings -- if the rotors were warped you'd feel a pulse in the lever as you brake.

or it could be a "cupped" tire. Check the air pressure, it should be at least 32 and no more than 40 PSI. Inspect the tire and see if it has any ridges or high spots. The left side of the tire will wear more quickly than the right since the roads are crowned in the center to allow water to run off

As above............ to check the head bearings for play, put the front wheel against a wall (the bike facing the wall) and push forward toward the wall the only movement the forks should make is by there own compression. If there is any other freeplay then you have some wear on the head bearing.

If a tire is cupped it could cause this problem since it will be under a load as you brake and the bike weights the tire. Motorcycles are single track vehicles and if the tire is cupped it could cause the front end to wobble a bit under braking, or if the air pressure is low. The tire is not supported by the sidewall, it is air that supports the carcas..

Or while your are riding, just throw yourself over the bars and inspect the brake rotors and pads at speed, just try and not get run over..


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10,000 miles.... I'm not disagreeing with the steering head bearing, that's you best bet here. I'd look at that and remove the front calipers to have a better look at the pads and rotors before I started taking it to a shop.

Steering head bearings. I think the previous owner did a few wheelies.

What do i look for when checking out the steering head bearing? Would i need to replace it? or can i just refurbish it myself? pretty much this bike is in my own hands in order for me to fix. I looked at the brake pads and they got plenty of pad left....im gonna have to check the rotors tomorrow for sure......i was testing the brakes after i sprayed some degreaser on them and it seemed a little bit better.(is that a hint for anything?).

To check the steering head bearings on my bike, I put it on the centerstand and use a scissors jack to lift the front engine pad. That lifts the front tire off the ground. Then I sit in front of the bike and grab the bottom of the front forks and push/pull. Any movement shows loose bearings. Then with the front wheel still off the ground, I turn the handlebars full left and right while listening and feeling for dry spots.

Yours doesn't have a centerstand so you have to figure out how to support the center of the bike without breaking any plastic and with the front wheel off the ground, but so the bike can't fall off. Some even hang the front of the bike from a strong garage beam. If you have to grease/change/tighten your bearings, you will need a service manual.

Limpz that is great! I actually laughed out loud at that one.

Slowpoke see above post, saves you lifting the bike.