Triumphrat

Blindboypig

Howdy all!
Well, it's probably time to do the brakes on my '99 TBS. However, before I engage myself in this black art I have a few questions to ask ya'll professionals
The front brakes work like a charm but the lever pull seems to be "stepped", i.e. it pulls a little, sticks, then pulls a little more, sticks, then pulls a little more. Not smooth like I'd expect. The rear brakes are fairly dreadful - will sluggishly slow me, but not stop me (I don't use them much anyway, but would prefer that they work if they need to).
I bought the bike used a few months ago and have no idea of it's previous service record. I'm guessing new fluid front and rear and front MC rebuilds (the right-hand cylinder weeps ever so slightly sometimes). Should I rebuild the calipers too? The pads are all in good shape (Ferodo sinters in front and organic in back).
Also, the TBS comes with SS brake lines, correct? At least the parts I see look like braided SS lines. I've heard that these lines do not need to be replaced. True or BS?
I've seen that Galfer makes lines for 2000 and up Thunderbirds - I guess that'd be the same as a '99 Sport, no? If I need new lines, I guess this is what I'd go with if anyone suggests it.
Anyway, before I pull apart the bike I'd like some comments on what you guys and gals would do. Like I said, the bike stops on a dime, but the fronts feel sorta "catchy" and the rear is pretty lame. I don't mind paying the money or doing the work, but I don't want to rebuild what doesn't need rebuilding. Thanks for any advice and insight!

-J

__________________
Ride Safe

Ballacraine

I never rate rear brakes very highly anyway TBH.

TBS brakes although adequate when new were never regarded as sparkling performers.

Despite the fact they look like four pots they are a con. They are one largish and one small piston on the one side of the caliper. I am on with an upgrade at the moment and am awaiting the opportunity to try out the results. ( Not been well enough to ride ) There are pics in my album.

I can't really answer for the performance of original BMC fitted to the TBS as I have never had one.

I started out with the original Legend single disc, then upgraded to a TBS front end using a 1/2" BMC from a GS500E Suzuki which was a noticeable improvement.

If you are happy enough with the performance I would give the system a clean up and fluid change and see if that helps.

Check that the sliding calipers are not partially seized. That could well give the symptoms you are describing.

HTH

Nige

__________________
In faecorum semper solum profundum variat.

(Always in the s**t it is only the depth that varies)

Nige's Gallery

JWoodsie

Yeah I would change the fluid, give the calipers a real good clean up, lube the slide pins in the calipers and go from there.
The "staged" feeling can often be just a sticking slide pin or piston.
PS and also dont forget to lube the lever pivots with a good quality synthetic grease, I use the same grease as I do on the slide pins.

[ This message was edited by: JWoodsie on 2006-07-04 14:56 ]

tridentt150v

Front lines are braided, I seem to remember that the back line isn't [I'll have to have a look and confirm later].

If they are ss braided then you don't need to worry about your brake lines ever. They are basically a set and forget item.

I'd do what Woodsie and Bally reckon. I'd clean/flush the whole system out remove all contaminants, and renew the fluid. Then I'd grease/lube the pivot points etc. TBS brakes are barely adequate, they look like they would be teriffic, but its all show. This is disappointing considering the weight of the bike pushing it along.
On the bright side you could have the same weight and similar performance and be riding a SINGLE disc TB, now thats scary. When I rode my mates TB I thought I'd deployed a parachute, not hit the brakes :-D

__________________
tridentt150v,
Great Southern Land.
(Where women blow and men chunder).

JWoodsie

Hey my brakes arent that bad.....you just need a strong right hand.

jimmyj900

I'd remove the front brake lever and take a close look at the lever itself. Check that the pivot hole hasn't worn out of round, that the pivot screw isn't worn, and that the tab on the lever that actuates the master cylinder piston isn't worn and grooved. If you find wear, replace the lever -- don't try to grease and re-use it since wear accelerates once it starts.

If the master cylinder piston is actuated by a rod between the lever and the piston (I don't remember), you also need to examine the rod and bore for wear and/or crud and corrosion. Clean, grease or replace as necessary.

The manual says you've got two piston sliding calipers up front, so it's possible that your sliding calipers aren't sliding properly. That calls for a disassembly, clean and lube of the sliding parts.

I'd strongly suggest that you don't try replacing fluid or rebuilding the master cylinder or calipers until you find out what's sticking! You may introduce new problems that could complicate things considerably.

Jim

__________________
CAUTION: This post may have been altered and critical safety information deleted without the permission or knowledge of the author.

bobsyouruncle

This sounds a lot like my TBS that I just got less than a week ago. Yesterday I bled most of a 12 oz bottle of DOT4 through the system, and it feels much better now. Both left and right sides bled brown at first, then once the clear stuff came through, the lever started to move more smoothly. Haven't had time for a road test yet, but at least the lever moves more smoothly :-D

__________________
Most people generalize
http://www.worldwidewords.org/qa/qa-bob1.htm

Blindboypig

Thanks for all the replies guys!
As soon as the weather clears up and allows me to step outside for more than a minute without the skies opening up, I'll start checking things out. I know I probably need new fluid, so I'll start with a fluid change and lever check and go from there. Thanks for the tips!

-J

__________________
Ride Safe

Mojoinco

Aside from the serious stuff, youse guys need to ride an old whore Hardly Ableson. That would create a Manly Grip, and possibly a highly optioned colored seat cover. Seriously, I've always had fun with late braking and find mine pretty good. I don't know if the pads were original (it had ~ 10k on it when purchased). Other than adjusting the lever and changing the fluid they seem to work great.

Keep in mind that if you want easier to apply brakes, you go down in bore size (mine is a 1/2" bore). If you want more pressure (less travel for the same volume) then you go up in bore diameter. For whatever reason, they are generally sized in 1/8" increments. In the case of my old Harley I installed some nice and soft Ferodo pads. My handshake was not so manly then, but I digress. I replaced pads with each front tire change, but it stopped then. So the step after insuring you have a fundamentally sound system would probably be best done with new pads.

On the rear brake, the one actuated by the strongest aprt of your body, but which adds maybe 30% of your braking power, I find that I have never had an issue locking it up on any bike when the pucker factor reached the power factor brakeover point [sic] and locked it up (oh, the poet laureatte that blows in me -- not what my wife would say blows out of me).

I have found (remember that old harley?) that sometimes one must disassemble the caliper to get it clean, including sediment that can build up on the bore in the area that the cylinder DOESN'T travel in (due to pad wear). This can cause the cylinder to hang up when you install new pads. Usually a thin board/paneling inserted between the pads (or between the caliper and piston) to keep from damaging the cylinder when it comes out (limits travel), and an application of compressed air (air gun with rubber tip applied to the hose fitting) or just pumping the master cylinder (only works for the first caliper). Makes a mess so do it over an oil pan and cover with a large rag to keep spray down.

Have fun!

__________________
Yee-haaaaa!