Hi Kai,
Not quite true...
Before his bearing was copied w/o his agreement, Joachim Gunst told me
that the bearing manufacturer recommended the preload be increased. You
may remember the original preload was 15mm of spring stretch, and was
later increased to 30mm of spring stretch. Joachim told me that the
bearing engineers were concerned about failure w/o the proper preload.
To repeat, this was months before his bearing was copied, and was part
of their investigation of a possible bearing failure. The bearing
manufacturer's engineers concluded that the bearing had, in fact, not
failed, and it's behavior was normal. Nonetheless Joachim gave the
fellow a new one.
I don't believe for one second that the manufacturer of Joachim Gunst's
bearing recommends that it should be used w/o preload. I know who copied
Joachim's bearing, I know what Joachim thinks of him, and I wouldn't
believe a word he says. I'll put my money on the fact that it's just
easier for him to sell it w/o the preload kit.
One of the list members bought a Gunst bearing from me and later
complained about it squeeling. His mechanic installed it w/o the preload
kit.
Don Malling
Kai M. Radicke wrote:
>>What about the BPNW kit, isn't it the same?
>>
>>GH
>
>
> Yes, and no. The bearing and sleeve appear to be the same, but the BPNW kit
> does not include the preload spring and the preload strap, or the extra
> dowels and sliding blocks (from the latest Gunst revision). BPNW maintains
> that the bearing manufacturer says the bearing is not meant to be used in a
> 100% duty setup (spinning all the time), and that is why they do not include
> the spring and strap.
>
> I installed a BPNW bearing a few weeks ago, in a friend's TR6 in CT, and it
> audibly squeaked all the time except when the clutch pedal was pressed (and
> load was then applied to the bearing). I ended up copying the spring and
> strap setup from a Gunst kit I had in the shop and installed it on the car
> with the BPNW setup... the squeak went away.
>
> The more I get into this subject of the Gunst spring, the more I want to
> stay away from even the Gunst bearing, even though it is the highest quality
> bearing on the market. No one is giving an answer that agrees, Gunst says
> the bearing should be preloaded and spinning all the time, the manufacturer
> does not.
>
> So if you buy the BPNW bearing, and it squeaks, you are kind of left looking
> for solution to stop the noise... the solution is obviously the spring and
> strap, which they do not include. But as I mentioned in a previous email
> about the Gunst bearing, no one knows the life span of these bearings, the
> most accumulated miles I know of on one of these bearings is about 10k
> miles... which is not much. I do not want to hear about failures in a few
> years because either the bearing should be preloaded or is not preloaded,
> and no one can agree.
>
> Kai
>
> --
> Kai M. Radicke
> Wishbone Classics
> www.wbclassics.com
> Ph: 215.945.7250
Check out the new British Cars Forum:
http://www.team.net/the-local/tiki-view_forum.php?forumId=8
|