1BigDog Posted April 24, 2012 #1 Posted April 24, 2012 IM considering doing the VMAX rear upgrade. Those who have already done it, are you happy with the results?
MikeWa Posted April 24, 2012 #2 Posted April 24, 2012 With out a doubt the best upgrade I have ever done. Mike
bongobobny Posted April 24, 2012 #3 Posted April 24, 2012 You'll be a little feistier off the line, and your RPM's will be up for the same MPH, but it makes the top gear soooo much more functional! Didn't do mine but the late JGorom did his and I got to experience it...
KAWoodworth Posted April 24, 2012 #4 Posted April 24, 2012 That was one of the best mods I've made. I was constantly down shifting with the stock rear, and now I hardly ever have to. You will need to watch out for the rev limiter, it comes up really quick when you crack the throttle wide open!
Freebird Posted April 24, 2012 #6 Posted April 24, 2012 I've had mine done for several years now and have never regretted it. I also have the Dyno ignition module so the rev limiter hasn't been a problem either.
msshearin Posted April 24, 2012 #7 Posted April 24, 2012 ok I'll bite.......what is the Vmax upgrade???????
Flyinfool Posted April 24, 2012 #8 Posted April 24, 2012 ok I'll bite.......what is the Vmax upgrade??????? It is what the 2nd geners do to TRY to catch up with a 1st gen......... It is taking the rear end from a V-Max and putting it into your RSV. The V-Max has different gears with a numerically higher gear ratio to let the engine rev a little higher so it is like you are always in a slightly lower gear.
KIC Posted April 24, 2012 #9 Posted April 24, 2012 The best mod for a venture....... ...is to upgrade to a 1st Gen.....
lsutley Posted April 24, 2012 #10 Posted April 24, 2012 I swapped mine for the VMax pumpkin last year. One of the best modifications for anyone pulling a heavy sidecar (IMHO). I was constantly down shifting in slow moving traffic, "in town" situations and most certainly hills. The previous rpm range, in top gear, was 2500 traveling at my normal highway speed. With the VMax gears the rpm's are in the 3000 range, where my rig makes enough power to cruse nicely and responds to a twist of the throttle without always shifting. If you have an older rig without the Zerk fittings in the rear suspension arms, the time to do it is when the pumpkins are swapped. There is a shim kit from skydoc, that may be needed to make the proper alignment to the axle line of center, when installing the VMax unit. Many thanks to those members, that supplied all the information that was needed to make my swap as easy as it was.
gator06 Posted April 24, 2012 #11 Posted April 24, 2012 Just did mine this winter, by far the best mod you can do for your RSV. If you pull a heavy trailer this mod should be seriously considered. I do not feel the wind resistance as much ether. My first tank this year got me 39 MPG, better then last year ( I ride hard ). If your looking for quick starts and more performance you will need to upgrade your clutch and install a Dyna ignition. I enjoy it. PS. You will pull ahead of a stock Harley
msshearin Posted April 24, 2012 #12 Posted April 24, 2012 oh ok I see....maybe I'm just old but ain't that a lot of time and money just to get a little more umph from a touring bike? I can go through a 35mph (at 35mph) and never downshift from 5th gear as long as I ease into it when speeding back up to 55. Just saying.....
GeorgeS Posted April 24, 2012 #13 Posted April 24, 2012 Isn't it true, that there were changes in the upper gear ratio's of the 2nd gen bikes, from the 1st year of production, up to the present ??? If so, then the V-Max mod, might have different effects, depending on what year 2nd gen you own. My thinking here is that the mod would be a larger improvement, in driveability, for the later year 2nd gen models. Or am I way out in left field here ???
Tartan Terror Posted April 24, 2012 #14 Posted April 24, 2012 I want happy at all. I actually took it out and sold it. I found that if you arent a aggressive rider that always wanted it in a very high rpm over 70 then it is no good. I would love to see a ratio between the original and the Vmax. Know that wont happen so I thought the original was better after trying the Vmax.
MikeWa Posted April 24, 2012 #15 Posted April 24, 2012 Ratios are 3.33/1 vs 3.66/1 So it is not a major gear reduction. It just puts the v-4 engine closer to it's usable power band (think power to weight). The gear teeth are Venture 10 pinion - 33 ring, v-max 9 pinion - 33 ring. Since they both use a 33 tooth ring gear no changes in the speedometer were seen. After using the v-max gear for a while here is my experience. 'The Dyna module I purchased hasn't worked so all my riding is with the stock module. I hope to see some additional improvement when I get the Dyna issues resolved.' The bike really came to life when I made this change. Fifth gear is now very usable from under 40 mph up until I am scared to go any faster. The rev limiter is much easier to find when thrill riding. That is not just because of the 400 rpm increase but also because the engine gains speed faster. It just feels like it is still very happily winding out when the limiter hits. Oh darn. Cruising at 50 or 60 mph in fifth is now quite comfortable. The bike will accelerate smoothly without down shifting for most normal maneuvers. There is a short, very short, learning curve as you get used to the sound and feel of the engine. My fuel mileage actually improved slightly. Probably because a higher gear can be used at almost any speed. I now frequently cruise around town at 35 or 40 mph in fourth and sometimes fifth. 70 mph equates to 3500 rpm in fifth and the v-4 is very happy there. This is an engine that is still making torque and horsepower all the way past 6000 rpm. It would be quite happy cruising at 4500. The bike still makes 90 mph in third and 100+ mph in fourth. But now fifth has some power so I have not actually seen that loss of speed at the top end. Mostly because I am chicken to ride that fast, although I have had the speedo over 110 when passing. Traffic jams with stop and go traffic are easier because I can ride slower without clutching. The engine just works easier with the small increase in rpm. I have not been on an extended trip at 80+ mph since making the change. I have however run at 70+ for over three hundred miles at a stretch. And I can report the bike just feels great with plenty of power in fifth gear. And I have to say 3500 rpm in fifth (Vmax gear) is just as fuel efficient as 4000 rpm in fourth (Venture gear). I don't pull a trailer so I can't tell you how it is for that. Control is improved in the twisties no matter what gear you like to take them in. I think that's because the bike responds to the throttle better. Low speed cornering is also improved for the same reason. I am looking foreword to my next cross country trip. I am anxious to make a comparison at altitude with a heavy load etc. So instead of a bike with a four speed transmission and a seldom used overdrive I feel I now have a bike with a very usable five speed transmission. And I really like it. More torque on the bottom and more power on the top. More fun and improved fuel economy. For me this has been a good change. There is a very good article in the tech section by Freebird detailing the swap. If you are worried purchase a core from e-bay and send it in for the gear change. Once you have the modified pumpkin you can install it yourself or most shops can do it in under an hour and a half. Mike
Guest Posted May 15, 2012 #16 Posted May 15, 2012 So, after reading all of your comments I decided to buy a spare final drive from a member here. (a more reliable member I may add). It arrived today at Sportmax in PA, the guy who does the conversions. I spoke to John Furber on the phone and he had it ready to ship late this afternoon. He took the time to answer all of my questions. Cant beat his service with a stick.
gator06 Posted May 15, 2012 #17 Posted May 15, 2012 Love it, Gas mileage up a little. Cant wait to pull my Aspen and not have to down shift.
woody071585 Posted May 15, 2012 #18 Posted May 15, 2012 Just did mine this winter, by far the best mod you can do for your RSV. If you pull a heavy trailer this mod should be seriously considered. I do not feel the wind resistance as much ether. My first tank this year got me 39 MPG, better then last year ( I ride hard ). If your looking for quick starts and more performance you will need to upgrade your clutch and install a Dyna ignition. I enjoy it. PS. You will pull ahead of a stock Harley My dad has a Honda silverwing moped that blows blows Harleys out of the water keeps up nice to the Gl1500 lol
Buck_Roy Posted December 2, 2012 #20 Posted December 2, 2012 Can anyone tell me roughly "about" what this mod costs to do?
JohnT Posted December 2, 2012 #21 Posted December 2, 2012 ...is to upgrade to a 1st Gen..... That covers it.
JohnT Posted December 2, 2012 #22 Posted December 2, 2012 Um, OK. I am no expert so I have a few questions. How on earth can increased RPM translate to increased mileage? "My first tank this year got me 39 MPG, better then last year" (And if my 1st gen drops to 39 mpg I will fix whatever has gone awry.) Are the second gens really that anemic? I hear (and participate in) all the razzing, but I have never ridden a 2nd gen. Or raced against one. Is 5th gear a bit tall on my 86? Yep, sure is. But that works really well at 75 on the highway. Or as someone pointed out, pulling from 30 or 35 back up to highway speed. And just as soon as I win the lottery I will cure that lack of power that I don't have by trying to shoe horn a V-Max 1700 cc mill into my 86.
Rosie1965 Posted December 2, 2012 #23 Posted December 2, 2012 Love the final drive upgrade on my first generation!
bongobobny Posted December 2, 2012 #24 Posted December 2, 2012 Can anyone tell me roughly "about" what this mod costs to do?There was a guy in PA that was doing it for $800 exchange but you had to bring the bike to him. The cost is pretty much what you can find the rear differential for...
Freebird Posted December 2, 2012 #25 Posted December 2, 2012 RMSPORTMAX is doing them for $300.00 exchange. That is where I got mine several years ago. Paul is great to deal with. http://rmsportmax.com/gateway.html
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