1st Gen vs 2nd Gen

[Hotrod]

I have read a lot of the posts on this subject and have not seen a direct question or answer on this subject, so here goes. Most say that the 83 to 85 1st generation is the fastest of all the Ventures at 1200cc. So my question is this.What has to be changed to get the hp of the 83 to 85 models in a 2nd gen? I know the gearing is different, and a lot of people change to a v-max rear end. I'm talking about just hp and torque increases. I've heard about swapping to v-max cams,but would like to know what all would need to be changed,how much of an increase could be expected,and if it is worth the money involved to warrant it. I know that Pegscraper has done a lot with his early model Royal Star,and was wondering if any one with a 2nd gen had tried some of the same things. I would like to know what the differences are and how to get, at least close, to the 1st gen hp and performance and approximately how much it would cost with 100cc more to work with.

[Sylvester]

The early first Gens are faster, the later are marginal. I have a good friend with an 06 RSV that will whip any of the 1st or 2nd gens. BUUTT he has a built 1500 cc PCW engine with a V-max rear end. And he has an additional $7500 + in it.

 

[dingy]

Let me start by saying I have no direct experience with an RSV.

 

The main thing I see in the specifications that hurt that motor is 28 mm carbs. Edit, Service manual does show 32 mm carbs for the RSV, I errored in looking at Royal Star specs.

 

The 1st gens have 34 mm carbs. If the motor can't pull air into the cylinders, HP is going to be affected.

 

Cams will help, due to keeping valves open longer.

 

Next thing would be increasing compression ratio. This can be done without machining heads by using a thinner head gasket. Higher compression = HP.

 

Last suggestion would be a programmable ignition module. Most bikes are setup from the factory with EPA regulations being a prime tuning factor. Dynatek D3K7-5 or the Ignitech module would be a help.

 

Gary

Edited August 9, 2010 by dingy
edited carb size to reflect 32mm

[Squidley]

The 1st and pretty much only bolt on thing your going to do is install a Dyna 3000 Ignition module. You can advance the timing curve and bring the rev limiter up to 7500 rpms. The Vmax or FJR gears will help with off the line performance. They also help when fully loaded 2 up pulling a trailer. In a nut shell, buy a Dyna 3000

[bongobobny]

I guess you have to ask yourself, "How important is it anyway???" We are not talking a huge difference, but a noticable one albeit. Are you interested in being the fastest set of 2 wheels in town? If so you do not want a Venture, you want a VMax.

 

Spend enough money and you can have a V8 or a V10 sandwiched between your legs and have it somewhat resemble a stock venture, but why?? The Venture, 1st or 2nd gen will blow the doors of any stock HD except the VRod, and be very comfortable riding as well. Neither the 1st Gen or the 2nd Gen wil take a new Wing.

 

Invest your time and money into touring, which is what the Venture is really built for...

[ahoutzer]

Second gens have 32mm carbs, not 28.

[dingy]

Second gens have 32mm carbs, not 28.

 

 

I looked at Royal Star specs when I was creating post, my bad.

 

I added edit to my first post.

 

That is still a reduction, albeit not as much.

 

 

Gary

[Freebird]

According to the Yamaha specs in our history section which I took straight from Yamaha's published specifications, the RSV actually has more HP than the earlier Ventures.

 

83-85 - 90 HP 10.5:1 compression

 

86-93 - 97 HP 10.5:1 compression

 

99-Present - 98 HP 10:1 compression

 

I thought that weight might be some of it but:

 

83-85 - 911 WET weight

 

86-93 - 783 Wet weight

 

99-Present 807 DRY weight

 

It is still my opinion that the biggest difference is gear ratio. Also the fact that you hit the rev limiter way too soon plays a factor if you are actually running these things hard.

 

Even with the VMAX rear in my '99, I still run 500 RPM lower than a first gen at 70 MPH in 5th gear. I haven't compared the RPMs throughout the entire range.

 

The bottom line is that I think HP has nothing to do with it. The second gen has more than either of the first gens.

[dingy]

According to the Yamaha specs in our history section which I took straight from Yamaha's published specifications, the RSV actually has more HP than the earlier Ventures.

 

 

83-85 - 911 WET weight

 

86-93 - 783 Wet weight

 

99-Present 807 DRY weight

 

 

 

Service manual shows following weights:

 

83-85 752 wet

 

86-93 783 wet

 

RSV 869 wet

 

Something else has puzzled me before about the RSV service manual specs. The RSV has a 10.0 to 1 compression ratio and is listed as 216 PSI compression pressure. The 86-93 is listed at 10.5 to 1 compresion ratio with 176 compression pressure. The two sets of numbers seem to conflict.

 

Gary

[Freebird]

That weight for the 83-85 makes more sense. The others are probably correct. I agree with you about the pressure too....that makes no sense to me.

[BuddyRich]

I have to agree, Its the fact they limit the RPM's so much on the 2nd gens. If we could turn over 8k then we would be running about the same as the 1st gens.

[Guest jet man]

I have several upgrades on my midnight, and I can tell you she is by no means a slouch. 1. Vmax rear end gears. (Huge in terms of pulling power off the line, and trailer towing) 2. K &N air filters; I don't know if they make a real difference, but they can't hurt. 3. Dynatek 3000; raising the rpm really helps in passing ability when you need it. 4. Iridium spark plugs; seat of the pants tells me ya I like them a lot. 5. Morgan carbtune; keeping the carbs tuned is key to ensuring quick throttle response and little or no exhaust popping on deceleration.

Hope this helps, Jet Man

[Freebird]

I have the exact same modifications at Jet man. I think I have the rev limiter at 7250...maybe 7500...I don't even remember now. I think they recommend 7250 maximum though unless you install heavier valve springs. I'm pretty much content with the way my runs now.

[hig4s]

Something else has puzzled me before about the RSV service manual specs. The RSV has a 10.0 to 1 compression ratio and is listed as 216 PSI compression pressure. The 86-93 is listed at 10.5 to 1 compresion ratio with 176 compression pressure. The two sets of numbers seem to conflict.

 

Gary

 

actually PSI is not directly related to compression ratio, except in a given engine increasing the compression ratio will increase the PSI, but changing the valve lash and/or cam profile will also change the PSI without effecting the compression ratio.

[dingy]

actually PSI is not directly related to compression ratio, except in a given engine increasing the compression ratio will increase the PSI, but changing the valve lash and/or cam profile will also change the PSI without effecting the compression ratio.

 

In essence we are talking about the same engine. Bore & stroke are identical. Same basic head configuration.

 

That's a big difference for cams. Valve lift numbers are identical in the service manual for 2nd gen's & RSV's.

 

The RSV does list a cranking speed 175/r min. The 86-93 spec does not list any RPM's. Maybe they were spinning the RSV faster.

 

What is the rev limiter set at on a stock RSV?

 

Gary

[Squidley]

 

What is the rev limiter set at on a stock RSV?

 

Gary

 

If I'm not mistaken it's right around 6500 rpms, might even be a little less.

[hig4s]

In essence we are talking about the same engine. Bore & stroke are identical. Same basic head configuration.

 

That's a big difference for cams. Valve lift numbers are identical in the service manual for 2nd gen's & RSV's.

 

The RSV does list a cranking speed 175/r min. The 86-93 spec does not list any RPM's. Maybe they were spinning the RSV faster.

 

What is the rev limiter set at on a stock RSV?

 

Gary

 

But what is the valve duration and timing.. compression ratio is figured theoretically assuming valves are closed on the compression stroke from BDC to TDC. On the compression stroke the intake valve does not actually close until after the piston is passed BDC on its way back up. Just a degree or two of difference on intake timing can make a noticable difference on the PSI.

Edited August 10, 2010 by hig4s

[dingy]

But what is the valve duration and timing..

 

 

That is something that is not is the factory specs for the Ventures.

 

They are a different P/N from the 93 MKII to the 99 RSV though.

 

Gary

[hig4s]

Gary

 

Just reading your signature, How about the unknown knowns, the things we know but don't know we know them. Of course they do us any good because we didn't know we knew them.