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i had a chance to put some power vents from doherty machine on our v-rod when it was on the dyno today.. tim told me they were worth up to 5hp on evo motors. i did see a solid 3 hp.. i don`t know if they would help other v-rods as much because i am pretty sure i have diagnosed our recent power loss to ring seal.. i put a blowby meter on the motor and the running blowby was higher than it should be.. the power vents actually lowered the blowby slightly so i assume that is how they increased the hp.. i will be running them from now on because every little bit helps..
 

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Discussion Starter #3
I'm assuming these are them: http://dohertymachine.com/index.php?cPath=5&osCsid=58c12222ca064a9b94eacbca69db1772


If so where do they go? Do they replace an existing part?
yes the inline are the ones i was using.. the vent lines inside the air filter housing going to oil air seperater have to have the vents installed inline.. it takes a little innovation but does work.. you also need to put a clamp on the front breather line at the bottom of the air filter housing ..tricky to tighten but doable..
 

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yes the inline are the ones i was using.. the vent lines inside the air filter housing going to oil air seperater have to have the vents installed inline.. it takes a little innovation but does work.. you also need to put a clamp on the front breather line at the bottom of the air filter housing ..tricky to tighten but doable..
Got any pics, you should do a how to...
 

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Got any pics, you should do a how to...
no pics, i am always rushed when i work on the bike. i have to find time between customer jobs so if i have something that needs done i have to hurry before they roll another customer bike on my lift.. i did finally find out why we are down on power,, a blowby meter showed 2.6cfm blowby at full throttle a call to wiseco tech dept informed me lt should be about .5 cfm so the rings are overdue to be replaced. we have a couple more races to make this year and then i will get the motor pulled and take it home to rebuild it..i won`t know if the powervents are worth as much power on a motor with good ring seal until i get ours going again but in theory they should make a measurable increase in power on a tight motor too.
 

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i had a chance to put some power vents from doherty machine on our v-rod when it was on the dyno today.. tim told me they were worth up to 5hp on evo motors. i did see a solid 3 hp.. i don`t know if they would help other v-rods as much because i am pretty sure i have diagnosed our recent power loss to ring seal.. i put a blowby meter on the motor and the running blowby was higher than it should be.. the power vents actually lowered the blowby slightly so i assume that is how they increased the hp.. i will be running them from now on because every little bit helps..
Thanks for the post and your findings. THE POWERVENTS are a well proven product, I designed them in 1998 the because of the issue''s with the EVO's and we have sold around 50,000 of them, thus far. the key to there success has been two fold. They are "very air senitive" in terms of the small PSI of air discharged from most engines, litterally any air movement will open them and even the smallest amount of incoming will lock them shut, thus preventing on the upstroke cycle to injest atmosspheric air The other is they last typically for years on end. Before the Twin cams came out we damn near wore out the dyno testing this simple product. but certainly always saw good results, the sporsters made even more power. The Twin Cams benifit as well but typically lesser gains. We even have them installed on our shop compressors, I guess I will make a kit specically for the v rods ASAP, ANY TAKERS? Tim Doherty
 

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I would be interested in a set... Always looking for a few more HP.....
 

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I would be interested in a set... Always looking for a few more HP.....
I need and want to get set up as a vendor on this site. (BTW I have called and e mailed with no response) We have a pile products already developed for the v rod, absolutely no junk. I have never introduced ANY product that does not perform as we say it will, PERIOD, and never will, nor will my son. Oddley even with todays off the wall GARBAGE, (some, not all) when we ship a part it is accuratly described, frankly for me its not about big profits but Pride. As i have mentioned I love this site, so many informed people. Thanks Tim Doherty
 

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I'm intrested

I need and want to get set up as a vendor on this site. (BTW I have called and e mailed with no response) We have a pile products already developed for the v rod, absolutely no junk. I have never introduced ANY product that does not perform as we say it will, PERIOD, and never will, nor will my son. Oddley even with todays off the wall GARBAGE, (some, not all) when we ship a part it is accuratly described, frankly for me its not about big profits but Pride. As i have mentioned I love this site, so many informed people. Thanks Tim Doherty
I would like to see what you have to offer.
 

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ISU
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how does installing a crank case breather make extra power?
 

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I would like to see what you have to offer.
First no the powervent is not like a PCV, a PCV WILL NOT AT ALL WORK(and is far to heavy to be activated by a motorcycle engine) many people, compare the 2 as the same. A pcv works directly oppisite of our vents, meaning it remains open when its pulled open under under fairly high vaccum and closes under deacceleration accociated with automobile engines. The Powerervent functions in a differtent manner. In brief the vent is pulled shut on the upstroke of the piston cycle, thereby not allowing atmospheric air to be drawn into the crankcase, on the dowmstroke the remaining air is exhausted out of the crankcase.
How can they make and improvement in power? Two ways, first the pistons are forcing less air out of the breather system (less resistance) second the pistion rings become more stable because the are being pressurized from the top and much less from the bottom. (less ring flutter) for those interested read up on pulling negative crankcase pressure using vaccuum pumps) The vents will not pull as much negative pressure but do go negative momentarly. Thanks Tim
 

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First no the powervent is not like a PCV, a PCV WILL NOT AT ALL WORK(and is far to heavy to be activated by a motorcycle engine) many people, compare the 2 as the same. A pcv works directly oppisite of our vents, meaning it remains open when its pulled open under under vaccum and closes under hard acceleration (low vaccum) and used primarily in automobile engines. The Powerervent functions in a differtent manner. In brief the vent is pulled shut instantly via suction on the upstroke of the piston cycle, thereby not allowing atmospheric air to be drawn thru the vents into the crankcase, on the downstroke it instantly opens allowing the remaining air to be exhausted out of the crankcase.
How can they make and improvement in power? Two ways, first the pistons are forcing less air out of the breather system, far less remaining air in crankcase, (less resistance) second the pistion rings become more stable because they are being pressurized from the top and much less from the bottom. (less ring flutter) for those interested read up on pulling negative crankcase pressure using vaccuum pumps) The vents will not pull as much negative pressure but do go negative momentarlly. Thanks Tim
Sorry I missed the part of this question. re parts

I will post pics of a number ot parts within 2 wks , 7 to be exact. The vent "kits" made specifcally for the v rods we have 17 left in stock, #162.00 complete kit, shipped.They are machined as a married pair, pretty cool, i may say, all hoses an fittings are included. if interestwd we can e mail a photo. Email josh @dohertymachine.com or call 800 956 9409 Thanks
 

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Here are a couple pics that Tim sent to me this weekend of the Vents. Wait until you guys see the rest of the parts in the works.





Ken
 

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Here are a couple pics that Tim sent to me this weekend of the Vents. Wait until you guys see the rest of the parts in the works.





Ken
Thanks Ken for posting the pics. Also please note you can also purchase our products directly thru him as well, same pricing, same great service. Thanks Tim
 

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are they as easy to install as just pushing the tubes on and that it or maybe a bit of a worm screw ,but easy done ,and why is one side on each side screwed out ,or are they all scew outable and thats just for the picture
 

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are they as easy to install as just pushing the tubes on and that it or maybe a bit of a worm screw ,but easy done ,and why is one side on each side screwed out ,or are they all scew outable and thats just for the picture
Brett the fittings t that are shown do screw in, those woulld be the outlet side, 4 worm clamps are included, the hoses are cut to lenght for installlation in the stock air box. Thanks
 
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