Triumphrat

TM · 10-22-2005

I visited my Triumph-dealer today (buying oilfilter) and took a closer look at a new S3-06 (white, very nice color btw) that they had on display. When I tried the frontbrake on the newer bike I immediately noticed that it had a completely different feel than the brake on the S3-05 (that stood beside the -06, and felt as mushy as my own -05). The frontbrake on the S3-06 felt like a front-brake is supposed to feel, not mushy at all, and the brake-handle was dialed in position 2 (whereas the brake-handle on the S3-05 was dialed in position 1)!!

I talked to one of the salesmen and asked him if Triumph had made any changes to the brakes prior to the S3-06. He told me he had just recently been at a national Triumph dealer-conference, and there was mentioned something about a change of brake-pump (probably pushing more fluid/stroke) on the S3-06 and that perhaps Triumph will replace older brake-pumps on the pre-06 S3:s. But it sounded like a hush-hushed big perhaps...

So, all you S3 owners with mushy brakes talk to your Triumph representative and keep your fingers crossed :wink:

[ This message was edited by: TM on 2005-10-22 15:23 ]

ELP_JC · 10-22-2005

I've read a couple of posts from '06 owners who report the same problem. I've never seen a change at mid-cycle, and I really doubt it'll be any. The master cylinder seems to be inadequate for the new radial calipers, so a tiny bit of air inside the system, which is also very likely due to the cheap 'T' split, creates the problem. The majority of owners don't report a problem, so the bike you tried must be one of the ones with a good bleed job.
Since I have big hands, and always use levers at the furthest extension, I don't think it'll be a problem for me.
Thanks for reporting the news, by the way.

Geof3 · 10-22-2005

I really think the issue is the bleeding. My dealer bleeds the brake with a compressed air system. I don't know which one. My brakes have been on 4 since the day I bought it. Spirited canyons and a day at the track and it hasn't been a problem. Mine is an 06...

crashmasterd · 10-22-2005

It's not the master cylinder, it's the calipers that are the problem. All of the fixes that have been tried and worked at all had to do with the calipers.

In addition, there's scuttlebutt out there about the new Daytona 675 having the same problem with mushy brakes. Note that it uses the same calipers as the S3, but has been upgraded with a new radial master cylinder and dual brake lines.

satansk9 · 10-31-2005

I have had a problem with mushy brakes with my 05. Didn't seem too bad, but then I replaced the Resevoir for a Rizoma one, and it has been getting gradually worse. To the point that I am a little nervous to ride with them as they are. My dealer called Triumph about it, and is waiting for a reply. I am dialled into position number one, and with smaller hands, I can grab a hand full of brake and almost touch the bar. Clearly something isn't right, as to whether it is something to do with the new resevoir or not, I don't know. I guess I will find out. The triumph mechanic suggested that he will bleed them again, and put in higher quality fluid......not sure if that will work or not.
'

Hairball · 10-31-2005

I put in Motul Racing DOT 4 brake fluid, took off calipers hung upside down from bars overnight, squeezed pistons, bleed the lines ( again ), worked great ....for a month or so.

I hope they realize its the calipers soon.

ELP_JC · 10-31-2005

My question is how can the calipers be the problem if there's no leak? Doesn't make any sense.
Based on the above symptoms, there's only ONE possibility: an internal leak on the master cylinder. NO OTHER CHOICE. Liquid is incompressible, so it can't be the calipers without fluid leaking out. And can't be air in the system if the system is bled, then performs fine, then gets mushy again shortly thereafter.

If I buy this bike, I'll change the master cylinder for a radial Brembo right away. Good day.

buzlin · 10-31-2005

This was posted by Tom Swan on T595.net

"excessive lever travel

This is nothing new, guys.
Seems more of the same old thing. Yes the other master cylinder that lilley sells (probably skyking too) will more than likely fix it at the expense of slightly less mechanical advantage over the calipers (read-less leverage).
To those that have never noticed Triumph uses the same calipers as other manufacturers, but uses a considerably smaller master cylinder (14mm vs 5/8"). Thats why they feel so powerful initially but over time develop lots of lever travel. Regular maintenance helps.
Over time the seals tend to hang or stick to the pistons, as the pads wear the pistons keep retracting to the same point, therefore you have to pull the lever further before pressure develops.
Sometimes the zip-ty on the lever will work, but more often than not I just unbolt the calipers and spread the pads/pistons apart then bolt'em back in place and pump them back up. Once you spread them you have broken the sticking seals loose , when you pump them a few times the pistons will then settle all the way out and lever travel will be restored. Of couse this has to be done with some regularity."

Take it for what it's worth.

ELP_JC · 10-31-2005

Buzlin, you just confirmed my suspicions; thanks for pointing it out.
However, as pads wear, lever travel should NOT change at all; what should change is the level of fluid in the reservoir. As pads wear, more fluid gets in the system to compensate the volume gained by the pistons being further out. Again, since fluid is incompressible, lever feel and travel should be identical with new than old pads.
The only problem that sticky pistons in calipers present is excessive rubbing against the discs, since they don't retract enough to avoid it, and brakes can overheat. So yes, every time you change your pads, you should clean the pistons too.

HarriS · 10-31-2005

JC, the lever travel SHOULD not change but in this particular bike it does. So it does with every bike with the same calibers aka 675 and Honda SP-2. One minute fix without unbolting anything is to push the caliber pistons in with pliers and pump them back out. This will fix it for a week or two but you eventually have to do it again.

The issue has nothing to do with master cylinder although a larger diameter one will mask the problem with some tradeoff in brake power. Nor it has nothing to do with air in the brakes.