Vmax engine vs. Venture Royal engine

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Jack Hammer

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I would like to know more about Venture Royale engine and converting it to Vmax. Whoever has done it, I would very much like to know more please. From the ground up if you have the time.

Comp ratios, head swap (heads or only cams?), small things, benefits, downsides. Oddities for power adders, whatever. I would like to know, that's all.
 
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Let's say if I wanted to build a twin turbo engine into a Vmax frame, which engine would be better? I'd personally think if Venture exhaust ports are facing outwards the frame instead of straight, that would benefit simpler exhaust for side mounted turbochargers. Maybe.

Additionally, are there any applications for double cam chains instead of singles?
 
The 1300cc Venture engine is a cheap way to go, not worth the trouble to do a 1200cc Venture into a VMax frame, unless you just want to get your bike back on the road with 'something.' No replacement for displacement.

The VMax heads fit the Venture, and I believe the VBoost can be adapted, but there are some fitment issues, Sean can fill you in.

I expect the Venture compression ratio is less than the VMax, an advantage if using forced induction.
 
The 83-85 Venture 1200's are lower compression then the 85-07 Vmax. Not worth bothering with unless you want boost on the cheap. The bores are the same so you could swap those pistons into a Vmax block or move some of the Vmax parts over to the Venture bottom end.

The 86-93 Venture 1300's are same compression as the Vmax but with smaller valves and smaller cams. There is enough clearance to swap the Vmax heads/cams over. The trans ratios are similar to the Vmax but with some small changes. Not enough to bother with swapping over. The dog design is similar to the early 85 vmax's that were recalled. They left them alone in the Venture (basically proving they are just fine if you aren't beating on them). Usually best to move a Vmax trans over but we've built a number of the conversions and they have held up just fine with the venture trans.

The shifter shafts are located differently on the Ventures with them coming out of the hole in the lower rear section of the stator cover. On the 83-85's they didn't even bother putting the hole in the mid gear cover. The 86-93 ventures had the hole in the mid gear cover and just not used (and no shifter shaft bushing was installed). They stator had two bushings and one can be removed and moved to the mid gear cover to be able to use it on the Vmax. To use the Venture engine block in the Vmax you would need to move over the shift shafts.
The

The PCV/Coolant Chamber between the cylinder heads has a different hose nipple to clear the vmax intakes with Vboost. Either move the upper section over or the entire assembly (easiest way).

The oil level sending unit polarity is opposite between the models. Swap that over or the light will not work correctly.

The vmax heads and cams are a LOT bigger and better to make power. The springs are also different but even the Vmax could use the upgraded springs. See picture of a Vmax head chamber being CC'd. I don't bother with the Venture.

The Venture used heavier rods. Not necessarily a good thing with the extra mass. BUT, again we've run them just as hard as the Vmax without any issues. The 83-89 Venture flywheels can be used on 85-89 Vmax's and a good option for blower bikes to help with the blower surging due to the heavier weight. The 90-93 Venture can be used on 90-07 Vmax blocks. Normally you would not want the extra weight on a natural aspirated engine.

The 83-85 Venture carbs are 34mm bores. The 86-93 Ventures are 35mm which match the Vmax but do not have a choke lever casting so you have to fabricate something to use a manual choke like the Vmax. Of course the Venture intakes aren't set up for cross flow so no Vboost.

There are other options with the Royal Star stuff that started in 1996 but none of them offer a performance advantage to the Vmax. No reason to use any of it. We've done a hybrid block with Vmax heads/cams and RS block but that required special pump elbow and we still ended up using a Vmax side cover on the stator so we could get the Vmax flywheel to clear and work. Someone smarting with an ignitech might be able to work out the timing events to make the RS flywheel work in a Vmax frame.

The RS does offer a few other trans ratios. The regular RS Venture has a good ratio set for big engines that can take advantage of the torque. The tour deluxe is what we use when we make the hybrid Vmax/RS with overdrive undercut trans set. The shift forks and drum with the regular RS Venture must also be used as there is just enough offset in the channels that they will not let a Vmax trans shift with the Venture forks/Drum (or vice versa). It's a complete swap or not at all. To use the RS TD 5th gear we have to alter the undercut to let it engage properly.

The Ventures did not have the stator cooling system that the Vmax has but it was offered by the dealer as a service component/upgrade.

There are oiling changes through the years but all can benefit from an upgrade like our HD oiling kit.

The starter clutch can be adapted from the RS to the Vmax but requires machining work.

The regular clutch from the 83-85 is a coil spring type (before Barnett sold their conversions) and can be retrofit into a Vmax though you can't swap the other direction without changing the clutch cover (which was shallower on the 83-85 Venture 1200's).

There are plenty of other tidbits and just depends on what your goals are.
 

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One2dmax,

Do you have a chance to confirm clutch axle diameter where the basket bearings run? 27,98mm?

Do you have new basket bearings? If not, then I will machine my own bearings. I found a little too much play in mine and took the clutch off.

The space to measure is somewhat awkward with the axle in the engine.
 
I do keep new bearings on hand (for the pressure plate). I do not keep the bronze inserts as they are not sold individually and usually the baskets fingers get worn and need a new basket before that bronze insert does.
 
Mine are still very good. So I'll make new bearings for it. Thank you for the info about bearing availability.
 
Are you able to put back in the oiling groves and oil reserve dimples?
 
I made it different to stock, made it my way. I didn't like the original groove design because they are too big in their surface area compared to axle surfaces. I wanted to reduce surface load and reduce tolerance. Already put everything together and put it through it's paces for about 100 miles. Quiet clutch is a great thing to have. More surface area, less wear, better power handling capability.
 
OK, so that is what you meant. I thought you were a troll too. This topic was already covered extensively in this thread earlier so you might want to read it from the start.
 
Yah I read thru it, was just looking for some clarification as mine is a 02 Royal Star Venture. Everything I’ve read talks about VMax stuff in 1st gen Ventures.
 
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