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 Post subject: Re: How Are These Pipes Made?
PostPosted: Fri Jul 13, 2018 11:22 am 
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lost1750GTV wrote:
does anyone know the weight savings of titanium vs stainless pipes?
must be considerable compared to stock.

Titanium weighs approximately 56% of equivalent stainless.

Weight savings approximately 44%.


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 Post subject: Re: How Are These Pipes Made?
PostPosted: Fri Jul 13, 2018 6:39 pm 
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thank you both -- so roughly 50% of !/2 the weight from stock?
yes, it would be great to have an actual comparative measurement from your set.
I recently purchased a stock bike, so if I can kill more stones with the same bird ..... Ok a more expensive bird.
but very light pipes and wheels (maybe CF?) may be sufficient without breaking banks.


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 Post subject: Re: How Are These Pipes Made?
PostPosted: Sat Jul 14, 2018 3:54 pm 
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As promised, I compared an upper pipe from JL in stainless steel with a similar upper pipe in titanium today.

Image

Here is the result for the stainless steel pipe - 1.40kg

Image

and now the titanium pipe - 0.75kg

Image

Assuming that the lower pipes of the RZ500 are a bit longer than these straight upper pipes, the total weight savings for a RZ500 set is ca. 2.80 - 3.00kg.


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 Post subject: Re: How Are These Pipes Made?
PostPosted: Sat Jul 14, 2018 5:20 pm 
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thank you, that is very much appreciated.
I'm not sure if there are many other easy ways to save an additional 6-7 pounds on a street legal "stock" bike, and that's a good chunk of the goal of 50 considering the laws of diminishing returns..


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 Post subject: Re: How Are These Pipes Made?
PostPosted: Sat Jul 14, 2018 7:58 pm 
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Simon Kvas:

I build these pipes during the summer in 2015. They were a total nigthmare to build as the upper pipes has to intersect to fit the beautiful Akrapovič silencers at the end. Everything is packed so tight They are made from 0.8mm thick cold rolled steel. Everything was done by hand, including cutting and rolling the sheet metal. It was absolutely one of the most difficult projects I have done.

The geometry itself is copied from jolly moto, as I had no experience in calculation of exhast for 125cc. Shape and curves were all done by me, I help myself with a model made from a steel wire.

Image


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 Post subject: Re: How Are These Pipes Made?
PostPosted: Sat Jul 14, 2018 11:33 pm 
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"total nightmare"
but very pretty


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 Post subject: Re: How Are These Pipes Made?
PostPosted: Sun Jul 15, 2018 1:55 pm 
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Can anyone post info about the shape of these pipes?

Image

I can only state the obvious.

The pipes look to be the same overall length. Does that mean they will both have maximum HP at about the same RPM?

The stainless pipe has a much longer (diverging) cone between the header and belly, and a shorter, fatter (converging) cone. Belly looks fatter, too. Not sure what these differences mean theoretically. Maybe the pipes were built for 2 different (state of tune) engines?

Wolfgang, are those JL pipes custom made for your bike, or are they regular JL pipes? Have you tried the JL and titanium pipes on the same engine?


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 Post subject: Re: How Are These Pipes Made?
PostPosted: Sun Jul 15, 2018 2:06 pm 
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Hi, yes the JL pipes are custom made for my 1999 YZR500 ANTENA 3 replica. The titanium pipe is original YZR500 works pipe, it does not fit on my RD500. I just have it for „decoration“.


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 Post subject: Re: How Are These Pipes Made?
PostPosted: Sun Jul 15, 2018 3:08 pm 
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Thanks. I understand, now.

Obviously custom JL, since it doesn't cross over. :smt003


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 Post subject: Re: How Are These Pipes Made?
PostPosted: Mon Jul 16, 2018 2:48 am 
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Actually, the works pipes are 2“ shorter in tuned length if you consider their stinger at the end.

Regards

Wolfgang


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 Post subject: Re: How Are These Pipes Made?
PostPosted: Sat Jul 28, 2018 3:44 pm 
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 Post subject: Re: How Are These Pipes Made?
PostPosted: Sun Sep 16, 2018 4:00 am 
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Been seeing references to KENNY ROBERTS HAND-CONED EXHAUST.

Does anyone have info on Kenny Roberts pipes?

https://www.ebay.com/i/292724527414?ul_ ... 2ffff52d8f

https://www.bansheehq.com/forums/index. ... one-pipes/


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 Post subject: Re: How Are These Pipes Made?
PostPosted: Sun Sep 16, 2018 4:55 am 
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I can hardly imagine that “King” Kenny Roberts is building pipes, and they look like BT pipes who built pipes for the MARLBORO YAMAHA team when KR was their champion rider


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 Post subject: Re: How Are These Pipes Made?
PostPosted: Mon Sep 17, 2018 11:52 am 
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These are the pipes listed as KENNY ROBERTS HAND CONED PIPES.

The 2 sets look very different.

Image

Image

Very strange. Maybe BT knows the answer.


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 Post subject: Re: How Are These Pipes Made?
PostPosted: Mon Sep 17, 2018 12:08 pm 
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mo matter who made them, that's one heck of a sand ... rail


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