4-Valve Hemi For Your V-Twin Engine

Who doesn’t want more torque and horsepower? A company called “Revolution Performance Motors” provides high quality 4=valve engines and head sets for your V-Twin needs. Their patented Hemi 4- Valve heads move 1.5 times more air than the stock 2 valve head.  Due to the hemispherical design of the heads and the position of the spark plug in the center of the chamber, engines are able to run less timing advance. This allows us to run higher compression without pinging or knocking. A 96 cu. in. 2 valve motor can make 70-80hp. The same motor with our Hemi 4 Valve Head kit installed makes 90-100HP. When it comes to getting off the line, our Hemi 4 Valve Heads give your 96 incher over 100ft/lbs of torque at 4000rpm. A 2 valve engine puts out about 90ft/lbs at the same rpm.. These  Hemi Head Kits will fit any Evo or aftermarket V-Twin engine up to 125 cu. inch. From 3.5" bore up to 4.25". RPM Hemi


35 Responses to “4-Valve Hemi For Your V-Twin Engine”

  1. 1 Rogue Jul 5th, 2007 at 9:05 am

    This style head was designed by Jim Fueling many years ago and I had the opportunity to do some Research and Development on them.
    I did numerous tech articles and was employed by two aftermarket motorcycle manufactuers who used them on their motorcycles.
    While the design of multipal valves did allow more air and fuel into the comustion chamber and the compression ratio was increased providing more performance there was always numerous problems with the package mostly in the rockerbox area.
    While the aftermarket manufactuers were using this style head the rockwell of the valves were changed as well as the swivel feet,rockerarm shims and other parts. There was numerous problems with these changes.
    The aftermarket companies went out of business and though there are many differences of opinion why the 4 Valve Head was felt by many to be one of the reasons.
    Officers of the companies had differences of opinion on how the head and rockerbox assemblies should be built.This resulted in them becoming very unrealiable.
    I do believe the heads when assembled correctly and using the correct parts do work well for certain engines. I did do a article on How To Accurately Build a 4 Valve Engine which was a use of words. I was employed at American Quantum at the time and they were trying to develope a 96 cubic inch engine.
    I went to Accurate engineering in Dothan Alabama and with the help of Berry Wardlaw the owner built a 96 cubic inch 4 valve engine and did the article.
    I might add that that engine is still running today which is a lot more than I can say for most of Quantum’s engines.
    I would suggest that anyone considering these heads look into them very carefully.Ask people who have used them and find out their opinion before buying.

  2. 2 Rogue Jul 5th, 2007 at 9:14 am

    For those of you interested in article on the 4 Valve Heads you can check them out at.http://www.bikerrogue.com/Articles/Tech_Articles/tech_articles.htm

  3. 3 Nicker Jul 5th, 2007 at 5:14 pm

    4 valve Deja vu….

    Around 1969 Rickman produced an aftermarket 4 valve head for 650 Triumphs. It topped off a VERY Cool looking 760 conversion kit.

    Despite lots of glossy pro-mo malarial and some press coverage it never took off. There were some rumors of valve push rod flexing issues at higher engine speeds.

    Some years later the factory introduce a 4 valve motor which looked similar to the Rickman head.

    An AMA racer running a factory motor told me it had RPM limitations.

    Perhaps 2 valves is simply more than one push rod can handle…?

  4. 4 Journeyman Jul 20th, 2007 at 8:47 pm

    I personally have been working on the Fueling designed 4valve heads since the very early 1990’s when I was a dealer for Rivera Engineering, who was at that time the distributor for the Fueling 4valves. Jim designed a very efficient head that was very capable of much higher performance which was later proven by Jim McClure, Bob Taft, and other record breaking drag bike builders and riders.
    Rogue and I were both working to improve the reliability of the 4valves, at
    the same time but my focus was trying to help the original owners of the Fueling heads, while Rogue was working for the manufacturers, trying to keep
    the quality to a higher standard. For the last four years I have addressed the problems that were raised one at a time, and have proven just as Rogue stated when these heads are assembled using modern materials and technology and set to the proper clearances, they can be very efficient and reliable. As a friend in the business once told me, if a proven product starts having problems don’t blame the engineers blame the accountants.

  5. 5 Rogue Jul 22nd, 2007 at 9:21 am

    Hey Journeyman.
    Happy to see you here.
    If you want to know about the Fueling design 4 valve heads Journeyman is one of the people to talk to.
    I got the number 8 set of heads that Fueling sold and did a lot of R&D on them for Fueling and later 2 aftermarket manufactuers.
    Journey man has also done a lot of R&D with good results.We have shared experiences and agree on what the problems have been and on ways to correct them.
    The problems I saw were from changes made to the kit from Fuelings design. Well there is a little more to it than that and to lengthy to go into here.
    To be fair to the new company marketing the heads I would have to see what changes were made if any.
    They have stated they have one bike with the change and on the road. The question now becomes how many miles on the motorcycle since the change and what problems have they run into.
    I suspect that like most companies when problems happen they will try to repair them and not post their trial and errors.
    My suggestion is to solve the known problems if they have not already before they start a heavy marketing campaign.
    There are some very qualified people in the industry that could be called in to help should they need it.
    Good Luck to them and I Wish Them Well.

  6. 6 Bruce Wolford Jul 30th, 2007 at 7:45 pm

    Our 1st Dyna Conversion now has about 350 miles on it. At 200 miles we tore the top end apart and noticed unusual wear on some of the swivel feet. We replaced them with a better design. Once we get another 50 miles on it, pwe owill tear it apart again. If everything looks OK, then we are going to let it go to 1000 miles before the next tear down.

    So far, the owner of the bike is just loving it.

    We fired off our 1st 114 last week. I fired right off on the test stand and is going into a custom as we speak.

    I have done the best I can to slow down the marketing department. But I can only do so much.

    Bruce Wolford
    Revolution Performance Motors

  7. 7 Nicker Jul 31st, 2007 at 2:58 am

    Is/was there ever any production OEM (besides Triumph)design that appplied one pushrod to two valves & Springs…?

  8. 8 dean Aug 7th, 2007 at 9:43 pm

    hi, i was wondering how much i how have to pay for a 96 ci hemi v twin engine ?, would u ship to australia


  9. 9 Dave Mcculloch Sep 2nd, 2007 at 5:34 pm

    Hi I have a set of the fueling 4 valve heads on my bike and am running the dual carb set up.I have now put about 3000 miles on the bike this year so far.I have had little trouble with them other than not knowing where to buy gaskets and o rings for the setup.I did however have a key snap on my pinion shaft and throw the cam timing out.That resulted in a major explosion.I had to weld the spacer and gear together for added strenght.This is the only weak point in the stock motor.After running these heads I will not go back to 2 valve heads ever.
    The design of the rocker boxes could be changed,the double swivel foot makes alot of noise but is liveable.The Yamaha v-twins use a rocker arm that has only one adjustable swivel foot and is very quiet.
    If the setup is done right they should go a long way without any major repairs.There are alot of bikes out there that have 4 and 5 valve heads that go thousands of miles without any problems.

  10. 10 Bruce Wolford Sep 18th, 2007 at 2:09 pm

    Dean, Our 97 CI Hemi 4 Valve sells for $7295. We can ship it to anywhere.

    Bruce Wolford

  11. 11 Journeyman Sep 18th, 2007 at 9:29 pm

    Dave, I am more of a R D man and machinist, but I do have all the support parts
    that you might need including upgraded gasket kits, swivel feet springs etc.
    I don’t advertise except by word of mouth. I have been doing this for 30 years 15 years of that working on the 4 valves. I am getting to the point I just can’t do everything I want to anymore so I just do what I can. What ever I can help you with I will be more than happy to share what has been done to upgrade the components of the 4 valve heads. These latest design improvements are now fully tested and are being installed in customers heads. There are hundreds of the Feuling heads out there and I am trying to find and upgrade them till all the original heads are taken care of first, then I will look into what to do next.

  12. 12 rayw Mar 22nd, 2008 at 4:27 pm

    I am getting ready to fit some rivera 4valves to my fxr ,I have contactded Dave mcculloch&rpm but would like to get in touch with journeyman thanks.

  13. 13 bill miner May 10th, 2008 at 10:46 am

    I have a 2000 quantum with feuling 4 valve heads. I need a set of head gaskets.Do you have or know where I can get some?

  14. 14 jim Jul 26th, 2008 at 8:33 am

    i bought a 01 american liberty and have been burnt by it, motor was put together wrong, wrong parts etc, it has the quantum heads on it and needs good swivel feet, just had it bored out 30 , motor only had 1059 on it when i got it, every shop i talk to here says gett rid of it or the heads and go to the s&s heads,,, enzo from webster charged me 50 bucks for one swivel foot (puke),,, could use some info on these heads and motor-96 s&s with jims crank

  15. 15 Todd Sep 12th, 2008 at 10:28 pm

    I just took in on trade a 1996 Kenny Boyce pro street bike with an original Jim Fueling built 4 valve hemi motor. I don’t know much about them. If anyone has interest in the bike call me.

  16. 16 Omar Jan 28th, 2009 at 5:40 pm

    I have replaced my quantum motor in my 1999 Liberty with a 96 S&S. Does anyone know what type of a 2 into 1 exhaust system will work with the Kenny Boyce frame without alot of modification?

  17. 17 Chuck Feb 16th, 2009 at 8:22 pm

    Journeyman / Rogue

    I have an early set of Feuling 4V heads never used… would like info on upgrades you had mentioned & install recommendations. Any help would be appreciated. Thanks, Chuck

  18. 18 Ron Young Mar 12th, 2009 at 9:37 pm

    I just took ownership of a 99 Quantum with the four valve heads and there is a lot of valve train noise that I would like to fix and would like to know where to get parts for the heads( o rings for the rocker boxes and or other parts) I cant seem to find anything on the net. Thankyou, Ronnie

  19. 19 jim May 15th, 2009 at 8:28 am

    The 4-valve set up fine,but the rockers and swivel feet adjusters are a joke, unless perforemance cycle just put cheap adjusters in, or set those up wrong too, this motor didn’t even have a front base gasket in it,,,,,,,,looking for good swivel feet

  20. 20 jim May 15th, 2009 at 8:39 am

    To Rayw, interested in what you have, to the journey man too, am interested in parts and right set up on adjusters,Rogue says .456, and are adjusters for VW race engines the same adjusters? my number is 585-237-6047

  21. 21 skulloz Sep 20th, 2009 at 7:44 pm

    I have recently purchased a set of Rivera four valve heads, that are missing the rocker arms,! where can I purchase some rocker arms to suit ,
    I have surfed the net but cannot find any part suppliers !!!!!!!!!!!!!!!!!!
    email me @ skulloz@hotmail.com with any info
    regards skull

  22. 22 rayw Sep 21st, 2009 at 2:05 pm

    Skulloz just emailed you

  23. 23 john c Sep 21st, 2009 at 7:02 pm

    has any one found out how to grt part’s for these heads. I have had to get all 8 valves custom made and with the gides it cost me $800. but now I need some swivel feet. I have the info from bikerrogue.com to set up the heads but also need the spacers. rogue has given me 2 places to call but I can’t get a hold of one and the other dose not want to sell parts unless I ship him the heads for him to do the work. if any one can help please e-mail me at ahounddog76@hotmail.com

  24. 24 dave mcculloch Sep 28th, 2009 at 4:58 pm

    Intake valves can be made from 883 to 1200 evo sporster exhaust valves.You need to have the collars cut down at a machine shop and the guides need to be knurled and reamed to size or you need to replace the guides to accomplish this.
    AS for other parts I keep checking the net or ebay to find these parts.

  25. 25 Kazoom Oct 4th, 2009 at 3:42 am

    Hi there, I started a Feuling 4 valve info thread a while back on xlforum.net that might be of help to some of you…


  26. 26 Pimpen Oct 22nd, 2009 at 4:57 pm

    Hi..Last year i bought a chopper with the Fueling 4-valve heads..its a 96″ sputhe engine with the Fueling heads, S&S flywheel,Shifton maximum cam, Dyna 2000i ignition, Mikuni hsr42 carb and a home made exhaus system.. it has 107hp on the rearwheel..

    Im looking for parts for the heads and i also want to know what kind of pistons that should be used with the heads? I dont think there´s that many fueling heads in sweden so there´s not so many to ask here ither haha!..

    Greetings From Sweden..//Pimpen

  27. 27 dave mcculloch Oct 31st, 2009 at 7:10 pm

    Try Journeyman.He has been around these heads for many years.Whatever pistons you use they will need to have new reliefs cut into them for the 4 valves.

  28. 28 Tony Sewell Dec 1st, 2009 at 11:58 am

    I have been running these heads for some time now and have had serious power, but these heads will break your heart. I have had loads of failures all revolving around the swivel feet. does anybody know where i can get some spare ones. I also do have a spare set of rocker housings with shafts and levers. mail me if your interested. pleas if anybody has access to the swivel feet supplier let me know. Is RPM still in buisness as there site is down and the mail address keeps bouncing back. tonys@valleytrucks.com

  29. 29 Kazoom Jan 3rd, 2010 at 5:36 pm

    Warning… for those interested in these heads, in the posts above… (journeyman/john mansell)…. this guy has had my money since July 2008 and I still dont have my heads or my 2 pistons I sent him over a year ago for a one hour job to cut valve reliefs. It is now january 2010. I have had nothing but problems and bs with this guy as soon as he got my money ($3187cnd). For anyone that needs more info… vascarperf@hotmail.com

  30. 30 Norm Teck Mar 24th, 2010 at 9:43 am

    RPM Hemi no longer distributes the kits or parts for the 4-Valve heads. They’re available, though. I’ll be posting distribution, installation, and technical development and improvement information on my website, http://www.teckbits.com/bike/quantum.htm.

    A lot of the problems observed with the 4-Valve heads and reported on this web site are dated and have been resolved by recent design improvements.

  31. 31 Jeff Starke Apr 19th, 2010 at 8:07 pm

    I have read many of these blogs now on the Feuling 4 valve, the American Motorworks 4 valve and the Quantum 4 valve. While I am amuzed at everyones comments. I like to say, that while many have put bandaids on the rocker issues. I have finalized the rocker arms and got rid of the swivel feet altogether. after the last 15 years holding Jim Feulings licence on the 4 valves and being the designer of the AMW and the American Quantum cycle company as the founder and developer, The members of quality mechanics that I have had the priviledge of working with and them working for me. has left a variety of opinions. over the years since Quantums demise by those I placed in charge of running the company. many have gone off in their own paths and declared themselfs partial and expert to the 4 valve.
    I remain still to this date the offical person that Jim Feuling resided the patents to. If there is any doubt just call Feuling Motor company and ask who has the 4 valve rights. or where you can go to get parts. they will give you my name and number. I maintain and sell support products for all Feuling 4 valve and the Jeff Starke, redesigned 4 valves that Quantum manufactured. Gaskets, o-rings, engine parts. and even motorcycle components are still available.
    What Happened at Quantum is everyone was an expert. things got changed and quality control personel weren’t even motorcycle savy. as the saying goes…. too many cooks in the kitchen, and the food gets burnt.
    In my absence after a Military Presidental recall that took me away from the company, I returned to a disassembled company that parts disappeared, and courts sold parts. none of which were released by quality control. I discovered that some of the parts were taken from the rejected quality inspections and people sold those parts to others at a premium price I understood. These parts were defective. and unfortunately put in motorcycles. The ones that took these parts and sold them didn’t have prints and drawings or tolerences to verify what they took. It was sad to see what I put 15 years into be disassembled while I am over seas serving my country.
    I have stayed quiet over the years and watched many come forward on these 4 valves and I thought perhaps it was time to speak out.

    I licenced the 4 valves to AJ Basile, at RPM Hemi and Renegade Cycle in Idaho, They got caught up in the same greed Quantum did among their shareholders. and never paid me for the license. I stopped them from purchase and machining the 4 valve components. and so the parts are available through me. I am the only official source. Any doubters contact Feuling Motor Company. I will agree with the many opinions stated in these blogs, that when the 4 valve heads are assembled correctly they will produce higher levels of torque over any 2 valve combination period. Over the years I have repaired many, I maintain a long list of satasfied customers that love their Quantums. Again when fixed right… they are great!
    Jeff Starke

  32. 32 dave mcculloch Apr 22nd, 2010 at 7:27 pm

    Hey Jeff
    Do you have all the components for doing a set of heads and can you do any machining on them.
    What is your contact e-mail.I have a set of heads that I would like to have the machining done by someone who knows what they are doing.
    Thanks Dave M
    E-mail addy is davemcculloch121@msn.com

  33. 33 Scott M May 2nd, 2010 at 3:15 pm

    I need parts for these heads. Gaskets, rockers, etc. Can you help? Jeff Starke or anybody else?

  34. 34 dave mcculloch May 4th, 2010 at 5:48 am

    Gaskets can be made up if you contact Copper Gaskets Unlimited. They are in Arizona and have a pattern for the gaskets for the upper and lower rocker box.I do not know where you are going to find rockers for those heads.
    Hope this at least starts to help you.

  35. 35 Jeff Starke May 6th, 2010 at 5:32 pm

    Everyone. if your looking for parts or contact for the 4 valves contact me at jeff@masterbikebuilders.com or call me 262-501-4500 Jeff

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