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Greetings,

 

Since I am planning to install 32mm carbs on my '99 Royal Star TC, from '99 or up Venture I thought that I may as well do the cams as well, and If I do the cams I might as well do the valve springs too, right? Well the springs (on Bike Bandit) are $25 per valve, that's $400 plus a set of cams from Ebay for $145, plus shipping. I can get a complete pair of "06 heads on Ebay for $250 plus shipping. Seems like a "no brainer", so naturally my question is, will the '06 Venture be a direct swap to my '99 RSTC? Thanks!

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Pretty sure I read somewhere that the 1st gen heads (IE; vmax) won't fit on a 2nd gen.

 

I want to say I read it on VMaxforum.net for some reason.

 

Something to do with the frame being in the way of the exhaust ports IIRC.

 

I think Dingy is trying that kind of hybrid, isn't he?

 

:think:

 

*Edit*

 

Found it: http://www.vmaxforum.net/showthread.php?t=26938

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The heads will bolt up to the block OK. After that it's going to get interesting.

 

The exhaust ports on the later Ventures is angled significantly outboard to allow the exhaust pipes to be routed outside the frame rails. VMax & 1st gen Ventures exhaust ports are 'straight' out, allowing the exhaust pipes to be routed inside the frame rails.

 

If the heads are on the block, then a 1st gen intake setup could be mounted.

 

It is right at physically impossible to mount a VBoost unit in a 2nd gen frame. Slim chance it could be done but the carb rack would need to be split in half and brought in from each side and then connected. I have tried doing it. There is not enough clearance to get a full carb rack under the center wishbone rail.

 

Gary

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It appears from the discussions that the issue is the engine mount. You may be able to get around the issue of the RSV down pipe is used, but I'm only guessing...

Attached picture shows what I did to front motor mount. On a 2nd gen, the two plates that I have mounted on the outside of the frame rails at the front mount points are connected by 2 tubes and mounted inside the frame rails.

 

I used long 1st gen bolts that go thru both plates with a tube that bolt passes thru to the 'exact' length between the solid mount bushings. This will allow the bolts to be tightened down without potentially causing the block mount ears to snap off.

 

Picture of unmolested 2nd gen attached.

 

Gary

20140415_205712.jpg

motor mount.JPG

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the heads will bolt up and the only differance will be the fronthead off the venture has the extra bolt holes for the dogbones that goes to the frame to help with the extra torque of the newer ventures. you can just swap out the cams and get the adapter plates a guy on delphi forms make for them. i've got a set of venture heads but never really look at it closely to see the differant in them.

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the heads will bolt up and the only differance will be the fronthead off the venture has the extra bolt holes for the dogbones that goes to the frame to help with the extra torque of the newer ventures. you can just swap out the cams and get the adapter plates a guy on delphi forms make for them. i've got a set of venture heads but never really look at it closely to see the differant in them.

 

Didn't see that one coming. :rotf:

 

Possible, but I have never seen a dyno run sheet for a stock RSV. :think:

 

Gary

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the orginal royals with the 28mm carbs and single cam springs puts out about 76 hp vs venture's 98 hp. I assumed that was the reason for the dog bones? on the '59 &'60 impalas they started putting a piece of chain around the motor mounts of the 348 ci motor because of the torque, then they bored it out and made the 409 ci motor.

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The 98 hp rating for the RSV's is bogus. It is first off crankshaft HP. This means it is setting on a test stand with nothing attached to motor that would drain horse power. No water pump, stator, clutch etc.

 

The 1986-1993 1300 1st gens were rated at 97 hp, again crankshaft reading. The general consensus here is that a 1st gen will outperform a 2nd gen in acceleration and high speed, hands down. This is supported by the facts of differences in construction.

 

The 86-93 had 35mm carbs and the RSV's had 32 mm carbs. That translates to the RSV's having only 83% area in each carb. Picture attached showing CAD drawing of venturi throat and size difference. Less air/fuel in, less horse power out in similar motors.

 

The motors are essentially the same with one other glaring difference. The RSV's had 4 into 4 exhaust system, which in general will drop HP another 10%.. Maybe not as much as 10% difference from the 86-93's since they tied into a common collector, but still not a HP advantage.

 

Picture attached of dyno HP reading only, no torque or AF readings, on a 1200 Venture (Early Tweety), pure stock other than K&N filter. It hit 81.65 rear wheel HP, this is 8 hp below the advertised HP of 89. Almost all manufacturers show advertise crankshaft HP, it is not real world.

 

Yamaha couldn't bring out the new & improved RSV in 1999 and advertize a lower HP than its predecessor, not a good marketing strategy.

 

Gary

1200 dyno.jpg

32 vs 35 bore size.jpg

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