Author Topic: Rad valve  (Read 2751 times)

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Offline runabout

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Rad valve
« on: March 29, 2012, 02:05:27 AM »
Well I'm having no luck finding a good replacement carb boot for the 88
K5 so I'm looking at the rad valve.. Opinions anyone? Other options if there are any?
Thx steve

Offline dave916

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Re: Rad valve
« Reply #1 on: March 29, 2012, 03:08:43 AM »

Offline runabout

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Re: Rad valve
« Reply #2 on: March 29, 2012, 09:01:16 AM »
I did not know that others fit the 88 k5..
can anyone confirm that they have used another year carb boot?
Thank you

Offline Motoroost1

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Re: Rad valve
« Reply #3 on: May 30, 2012, 05:27:34 AM »
I use a Rad valve on my 2003 K5 and I like it . I had to lean the jetting out a bit but other then that , no issues at all . Motor is very responsive . I use the FMF Gnarly woods pipe so I'm not sure if I'm getting all of the benefit of the Rad valve as I suspect that there could be additional power at high rpm ( I find that the Gnarly flattens out at high rpm ) . I also have a tuned up mint condition 2007 KX250 ( Rad valve as well ) that rips and the K5 will simply eat it . The mid range torque is incredible .

Offline dmazz71

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Re: Rad valve
« Reply #4 on: May 31, 2012, 01:59:56 AM »
I have an 3 too and also like the response that I have noticed.  Although, in my case, I made a few changes until I was happy.  I swapped out the Gnarly wood pipe for a stock pipe and switched to race gas, which seemed to compensate for having to rejet the carb. 

Offline Motoroost1

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Re: Rad valve
« Reply #5 on: May 31, 2012, 02:48:05 AM »
I've got a stock pipe as well but I've never tried it . How does it compare to the Gnarly woods ? My only complaint with the Gnarly is that I find the power flattens out in the upper midrange quite a bit .

Offline dmazz71

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Re: Rad valve
« Reply #6 on: May 31, 2012, 06:56:34 AM »
It doesn't hit as hard on the low end, but the stock pipe makes up the difference in the mid to top end.  Since I mostly ride in sandpits and a wide open MX track, the rad valve, stock pipe and race gas is the perfect setup for me.  It really all depends on what your powerband preference is.  I liked the arm ripping low end, but not enough to sacrifice the top end hit.  Just my 2 cents.

Offline Motoroost1

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Re: Rad valve
« Reply #7 on: May 31, 2012, 08:33:47 AM »
Most of my riding on the K5 so far has been on fire roads so I could go either way on power bands I guess . I like the low - midrange pull with the Gnarly pipe but I've been wondering what the bike would be like to ride with a stronger mid - upper powerband . I like this type of powerband on my 2007 KX250 but as I am new to the K5 , I was not sure if this engine would really be happy to rev out a bit . Perhaps I'll take an afternoon and put the stock pipe back on to see how it goes . I am interested to see how the bike works this way now :)

Offline dmazz71

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Re: Rad valve
« Reply #8 on: May 31, 2012, 11:12:07 AM »
If you're used to blasting down fire roads, I think you will like the stock pipe better.

Offline Motoroost1

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Re: Rad valve
« Reply #9 on: May 31, 2012, 11:35:11 AM »
My interest has now been piqued so I guess I'll have to try the stock pipe out just to see how it compares to the Gnarly . It should be interesting .