True rear horsepower test article - RD/RZ featured

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LC Cnd
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True rear horsepower test article - RD/RZ featured

#1 Post by LC Cnd » Mon May 21, 2018 2:46 pm

Came across this blog article on dyno testing calculating true rear horse power. Gives some explaination how the dyno numbers can be fudged and how this company is advertising how it can provide true rear wheel horse power. Bit an info mercial but an interesting read for those interested in how RD/RZ (350cc scale sample section) compare to other vintage & later bikes tested. TZ's highlighted. Appearently they were impressed with the RD/RZ's which had mods. Link: ... DwJ1OkcP8x" onclick=";return false;

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Re: True rear horsepower test article - RD/RZ featured

#2 Post by hondaror » Tue May 22, 2018 4:05 am

Yup. Every dyno is different, even the same models. They are good for the operator who runs it all the time. Consistency is really important. They are not to be shared by operators.
...and yes, the numbers vary like crazy. My stock 31K engine, according to my former boss' dyno, produced 56 ponies at the rear wheel. Another forum member here, commented that it was the hardest hitting RZ350 he'd ever rode. He used to race these puppies. I used to race RD LCs, TZs, and RZ500s. My RZ350 is a lot of fun.
According to my former boss' dyno, Steve's 31K RZ, puts out more hp, in the 60 range. They are close, and Steve has done more work to his. I've been on both bikes and they are fun. Much more fun then stock.
There are many big bore RZs out there that generate way more power. I've never had the pleasure of riding one of those to compare. I would also assume that the power characteristics are very different. People are so obsessed with hp figures. Torque is perhaps, more important. Equally important are platform mods. Fat wheels, stiffer forks are two factors that drastically change the bike.
I think what I'm getting at, is, how important are the numbers? I think, not extremely. What I find appealing, is the biggest bang for the buck mods. Not drastic changes to the platform, as that makes the bike fall into another class. I'm all about smart mods, with big improvements with little given up for the return. In other words, make it breathe and keep it reliable. It should be easy to ride fast. That in a nut shell is the key, in my mind.

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Questo vecchio rz
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Re: True rear horsepower test article - RD/RZ featured

#3 Post by Questo vecchio rz » Fri Aug 24, 2018 4:37 pm

IMO, there all just measurement tools. Ignorant people slag Dynojet, and vice versa.
I read that article maybye 10-15 years ago, It's interesting...but it reads as if it's a infomercial. Waiting for the buy now with 10 easy payments

What's curious to me is they state 50 h.p. for a ported/piped RZ350, which is their accurate measurement, but they claim 60 h.p. for a AprillaRS250 , a ported ,piped,carbed RZ 350 will easily out accelerate a RS250 no problem..
Doesn't matter unless your trying for bragging rights...which almost universally ALL competitive racers/ builders.... do.
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Re: True rear horsepower test article - RD/RZ featured

#4 Post by Hellgate » Sat Aug 25, 2018 5:58 am

That's not a blog site, that's a page from the Factory Pro site. Marc Salvisbergs site.

A couple of my old bikes are on that list." onclick=";return false;


'12 Tuono V4R APRC, '05 R6, '88 RZ350, '82 XV920R

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