ST1100 Front Disk Replacement

[ChriSTian_64]

My 2000 ST1100, non abs, only has 37 000 km, or 20 000 miles. I checked the thickness of my front disks, and they are due to be changed very soon.
I don't remember the minimum thickness in inches, but in metric it is 4 mm, witch is the thickness of 4 dimes.

So, I checked the prices of new ones on Partzilla and... they are at US $ 345 each. I need two, of course. Ouch !

But these are OEM... original Honda parts.... There migth be other brand, of good quality, for a bit less ?

This is the first time I will be buying new disks. So, I don't know wich brands to look for.

Of course, for Break and Tires, for obvious safety reason, these are two areas where I am looking for good quality, not the cheapest ones.

Any advices ?

Chris

 

[dwalby]

hopefully you can find a used pair online somewhere, otherwise EBC is another option, but they're still pretty expensive. I can't believe someone could wear out a set of rotors in 20k miles, are you sure that's the actual mileage?

Also, what do you mean by 'due to be changed very soon'? What's the current thickness?

 

[sirepair]

Get a caliper and properly measure the thickness. Unless you are EXTREMELY HARSH on the brakes, I seriously doubt that the rotors are done in 20K miles. The original rotors on my '93 lasted about 160,000 miles, with 60K of that with EBC HH Sinthered pads and braided brake lines. IIRC the minimum thickness is stamped on the rotors.

 

[ChriSTian_64]

I can't believe someone could wear out a set of rotors in 20k miles, are you sure that's the actual mileage?

What's the current thickness?

Hum.... Thanks dwalby. Since this is my first road bike, I had no idea how fats a disk can wear out. But, thinking twice, 20 k miles really isn't much. It doesn;t make much sense to have to change your disk after 2-3 sets of front tires.

Yes, I am pretty confident this is the real mileage. I am only the third owner. When I bought it, the rear tire was from 2002... and other signs also shows that this bike is still is pretty new.

Maybe I'm wrong about the minimum thickness of the disk. Let me check that again in my manual.

 

[ChriSTian_64]

Get a caliper and properly measure the thickness. Unless you are EXTREMELY HARSH on the brakes, I seriously doubt that the rotors are done in 20K miles. The original rotors on my '93 lasted about 160,000 miles, with 60K of that with EBC HH Sinthered pads and braided brake lines. IIRC the minimum thickness is stamped on the rotors.

160 000 miles ? Ha ! Very good news sirepair. So I should be good for ten other years. hi hi.

Yes, I do have a digital Caliper, a very essential tool, isn't it ?
I took a picture of the disk thickness measurement, last fall, before putting my bike in storage for winter.
Let me find that picture.

 

[ReSTored]

+1 on what sirepair says. My ST has about 140,000 km on it and the original disks, front and rear, are still within spec as measured by a micrometer.

 

[ChriSTian_64]

I had 4.74 mm, wich gives 0.1866 inch or approx 3/16 of an inch.

 

[kiltman]

My 1990 went 190,000 kms before it needed front rotors. I will measure my 2002 and see where they sit. I have 77k kms on it. I’m replacing the brake pads on it later this week.

 

[ChriSTian_64]

Well... here it is, in my Clymer manual, page 488 (first edition, 2002), chapter 14 : disk inspection.

The dimensions given in table 1 (front brakes) are for the standard thickness and wear limits.
And as mentioned by sirepair, they also say that the minimum thickness is stamped on the disk face.

So, for the front disks, the standard thickness is 4.8 to 5.2mm (0.19 to 0.20 inch) : so I am just a bit under the standard thickness.
And the wear limits is 4.0 mm (0.16 inch).

So, I am far from being there yet, as you all mentioned. That is a very good news...

So, my next BIG question now, is what else can I do whit the $800 I was expecting to spend there.

Just as a side note... I measured both front disks at differnet places, and was surprise to notice different thickness... well not a big difference, but... it seem to be normal.
My measurements were : 4.74mm, 4.64, 4.69. A fourth measurement gaved me 5.25. That one is more far apart.

 

[ReSTored]

I don't have my Clymer manual handy, but a quick web search indicates replacement spec is 4.0 mm...................... Yours is 4.74 mm, so you're a long way off needing new front disks.

 

[John OoSTerhuis]

I agree. At that mileage your OEM rotors should be fine. The rotors wear slowly with Honda pads. 190K statute miles on mine and still in spec. FWIW

John

 

[Andrew Shadow]

The Honda shop manual specification is 4.8 to 5.2 mm (0.190"-0.200") and the service limit is 4.0mm (0.160").
Yours are barely worn. Forget about them and go ride- after March 15.

 

[ChriSTian_64]

Excellent !

Thank you all of you.

Now Waiting for summer... in 5 months.

 

[sirepair]

A few things to consider for your farkle fund: Custom seat (Russell, Liam, Terry Adcox, etc.), Suspension upgrades, heated gear, GPS, or intercom.

 

[Andrew Shadow]

Christian:
Whatever happened to your backyard garage/workshop you were planning about a year ago. Did you ever build it?
If not- put the money towards that. If you have already built it- use the money for some toys like a motorcycle lift table.

 

[mello dude]

I had 4.74 mm, wich gives 0.1866 inch or approx 3/16 of an inch.

As others have said, your fine... you have thousands and thousands of miles to go!

 

[CYYJ]

Hello Christian:

4 Canadian 10¢ coins measure 4.8 mm thick on my micrometer. See the picture below.

A new ST 1100 front brake disc measures between 4.8 and 5.2 mm thickness. The minimum service limit is, as you noted, 4 mm.

I don't think you have any reason at all to be concerned. For what it is worth, the two front discs on my 2001 ST 1100 - which now has over 200,000 km mileage - are both original, and both within service limits. A lot of my riding has been in the Swiss alpine passes & German autobahns, which I think would result in more wear than riding on Décarie Boulevard.

Four ten-cent coins

 

[Upt' North]

Well... here it is, in my Clymer manual, page 488 (first edition, 2002), chapter 14 : disk inspection.

The dimensions given in table 1 (front brakes) are for the standard thickness and wear limits.
And as mentioned by sirepair, they also say that the minimum thickness is stamped on the disk face.

So, for the front disks, the standard thickness is 4.8 to 5.2mm (0.19 to 0.20 inch) : so I am just a bit under the standard thickness.
And the wear limits is 4.0 mm (0.16 inch).

So, I am far from being there yet, as you all mentioned. That is a very good news...

So, my next BIG question now, is what else can I do whit the $800 I was expecting to spend there.

Just as a side note... I measured both front disks at differnet places, and was surprise to notice different thickness... well not a big difference, but... it seem to be normal.
My measurements were : 4.74mm, 4.64, 4.69. A fourth measurement gaved me 5.25. That one is more far apart.

Sounds like you've got money for a ride and good brakes too.
Upt'North.

 

[Bmacleod]

Hello Christian:

4 Canadian 10¢ coins measure 4.8 mm thick on my micrometer. See the picture below.

... or 3.5mm in USD . Sorry, couldnt resist

 

[GGely]

Using that type of caliper doesn’t give a true representation of the rotor thickness, since the measuring surface is so long. Next to a proper brake rotor caliper, the next best tool for the job is a micrometer, preferably with a pin for one of the measuring points.

I use one similar to this one: