Author Topic: Couple questions about 74 cb550, some of these are general for most our bikes (Read 847 times)

andy8190 · « **on:** July 17, 2009, 09:48:31 PM »

1. My front brake has been pressing on my disc constantly so today i took it of and cleaned everything out with brake cleaner. How much force does it take to get the piston back into the caliper because it took a decent amount of force to pop that thing back in there? How freely is the front wheel supposed to turn if the brake is not engaged, because sometimes mine spins a couple revolutions and sometimes it will only spin around about once with a little decent force in the spin? It seems like the brakes are engaging but will not recall once the lever is released, what could be some causes of this?

2. When putting the front wheel back on today i notice i have about 2 or 3 millimeters of side to side movement of the center hub, is this normal or is there supposed to be a spacer that prevents this tiny bit of movement?

1timduke · « **Reply #1 on:** July 17, 2009, 10:02:46 PM »

If the brake does not bounce back, I'm thinking there is air in the line, or the bleed screw is still open.

I don't think there should be any lateral play in the hub, 2-3mm sounds like a lot to me, did one of the forks spin the other way possibly?

-Tim

andy8190 · « **Reply #2 on:** July 17, 2009, 10:11:00 PM »

the bleeder screw is definitely closed, there possibly could be air in the line. I have the lever tied down right now and will leave it over night to let all the air rise out.

The lateral movement is prolly more like 1-2 millimeters. As far as i know a fork has not spun. I will try and take a pic of the gap sunday and post it to show you the difference.

BeSeeingYou · « **Reply #3 on:** July 17, 2009, 10:20:27 PM »

It will take a fair bit of force to get the piston back in but you should be able to do it with your hands. The problem most likely is the caliper seal needs replacement. When you pull on the brake lever the seal stretches out a tiny bit with the piston and then acts to retract it when you let up. As they age they lose their elasticity and tho they may not leak they are shot. Make sure you clean the groove it seats in. It is also possible the return hole on the MC is plugged. It is the tiny hole closest to the outlet port on the inside of the MC. Use a small wire to probe it to see if it's open. If you need more info on this do a search this has been well covered.

andy8190 · « **Reply #4 on:** July 17, 2009, 10:31:21 PM »

my guess is the seal. I just got a new after market master cylinder so it should be fine. The seal on the other hand is prolly 20 years old. I wasnt able to replace it yet because i have to order a new one but it looks flat or squared, I'm sure it is supposed to be rounded like an o-ring?

andy8190 · « **Reply #5 on:** July 17, 2009, 10:47:35 PM »

thanks for the comments about the brakes, but does anyone have a comment on the lateral movement issue?

bryanj · « **Reply #6 on:** July 18, 2009, 05:14:11 AM »

Wheel bearings shot or spindle assembled wrong

Bill/BentON Racing · « **Reply #7 on:** July 18, 2009, 05:44:09 AM »

Wait for your new seal,it is not round like O ring ,round but flat top,bottom,and circumference,I guess it's a flat ring? Make SURE groove is clean and M/C return hole open,as someone said piston should go in by hand.Bill,Wheel shoul roll freely!

Popwood · « **Reply #8 on:** July 18, 2009, 08:31:58 AM »

Regarding the side to side play, did you put the axle nut on correctly when re-assemling? I just went through this-- long story-- but make sure the hex end of the nut goes to the INSIDE, toward the hub. It seems backwards but that's the way it goes.

andy8190 · « **Reply #9 on:** July 18, 2009, 05:41:57 PM »

i am going to check that right now

andy8190 · « **Reply #10 on:** July 18, 2009, 08:04:36 PM »

so i went out and god my axle nut was sooooooo lose, i am lucky my axle didnt fall out. that pretty much solved the problem. I can now spin the tire and it doesnt stop spinning for about 4 or more revolutions

Spanner 1 · « **Reply #11 on:** July 18, 2009, 09:54:28 PM »

Andy...!!!!, sheesh..!

andy8190 · « **Reply #12 on:** July 18, 2009, 10:40:08 PM »

yeah i know. I had no idea, just lucky I noticed it now.

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Author Topic: Couple questions about 74 cb550, some of these are general for most our bikes (Read 847 times)

andy8190

Couple questions about 74 cb550, some of these are general for most our bikes

1timduke

Re: Couple questions about 74 cb550, some of these are general for most our bikes

andy8190

Re: Couple questions about 74 cb550, some of these are general for most our bike

BeSeeingYou

Re: Couple questions about 74 cb550, some of these are general for most our bike

andy8190

Re: Couple questions about 74 cb550, some of these are general for most our bike

andy8190

Re: Couple questions about 74 cb550, some of these are general for most our bike

bryanj

Re: Couple questions about 74 cb550, some of these are general for most our bikes

Bill/BentON Racing

Re: Couple questions about 74 cb550, some of these are general for most our bikes

Popwood

Re: Couple questions about 74 cb550, some of these are general for most our bikes

andy8190

Re: Couple questions about 74 cb550, some of these are general for most our bike

andy8190

Re: Couple questions about 74 cb550, some of these are general for most our bike

Spanner 1

Re: Couple questions about 74 cb550, some of these are general for most our bikes

andy8190

Re: Couple questions about 74 cb550, some of these are general for most our bike