kevin-vic-b.c. Posted October 2, 2015 Share #1 Posted October 2, 2015 I had been told a number of times that the engine in the 1300 Ventures was a "de-tuned" Max engine. Seems logical... they look the same from the outside. So if that is true then why is a Vmax a 1200 cc and not a 1300 also. Is it due to to the different heads? Just wonder why. Link to comment Share on other sites More sharing options...
Yammer Dan Posted October 2, 2015 Share #2 Posted October 2, 2015 Venture was changed to 1300 in 86. Earlier were 1200s Link to comment Share on other sites More sharing options...
kevin-vic-b.c. Posted October 2, 2015 Author Share #3 Posted October 2, 2015 Venture was changed to 1300 in 86. Earlier were 1200s Yes I do understand that in 85 or 85 the Venture became 1300...... was the Max based on the original 1200 and never changed? Link to comment Share on other sites More sharing options...
Great White Posted October 2, 2015 Share #4 Posted October 2, 2015 I had been told a number of times that the engine in the 1300 Ventures was a "de-tuned" Max engine. Seems logical... they look the same from the outside. So if that is true then why is a Vmax a 1200 cc and not a 1300 also. Is it due to to the different heads? Just wonder why. Nope. Yammy essentially took the 1200 Venture engine and applied a lot of "old school hot rod" tricks to it to make the VMax engine. Some of the changes: Pop up pistons for compression bump, larger intake/exhaust valves, longer duration cams, larger ports, revised ign curve, larger carbs, etc. About the only real "new" thing they came up with for Mr Max was the V-Boost scheme where one cylinder can draw from two carbs above 6500 rpm. The rest is all old tried and true methods of squeaking more power out of an engine. Like most engines, all the power is mostly hiding in the heads.... A few driveline tricks too such as a lower rear diff gearing helps the 'Max move out with authority. Lower weight than a Venture doesn't hurt either in the 1/4. Interestingly enough, the VMax guys have been known to swap a 1300 block under a set of vmax heads for an easy 100 cc boost. As the old adage goes: there's no replacement for displacement (you forced induction guys don't count!) If anything, the 1300 is just a punched out 1200 with 1mm larger carbs.....punched out by installing bigger cylinder liners that is. Link to comment Share on other sites More sharing options...
cowpuc Posted October 2, 2015 Share #5 Posted October 2, 2015 Fair question indeed Kev,, hope you get lots of input and thoughts on the subject.. Here are a couple of mine.. The original Venture motors were 1200cc, the V-Max was developed out of that motor because it proved very durable with lots more potential for unsetting the then King of Muscle Bikes - the V-65 Honda.. Yam engineers thought about a turbo 1200, then some GENIUS at Yamaha came up with the idea for the V-Boost - IT WORKED AWESOME!! They UP TUNED the original Venture motor (not the other way around) with the boost, bigger carbs, bigger valves, different cam profile, heads and so on.. It had to spin up higher - the "boost" on mine doesnt really hit hard till around 8 grand - redline is 9.5.. The later MK2's got the bigger bore (went from 76mm to 79mm) which increased thier total cc to 1300.. The Max stayed at 1200 all the way to the end of its run.. Why? I would not be surprised that was simply because the Max really had no competition as the King of Crusiers for many many years. Suzy dropped the Madura, Honda dropped the V-65.. Sport bikes like the R1's, Busa's and the like took over - the Max is a totally different ride than those bikes,,,, kind of a lone king.. On the other hand, the touring bike market engine size demands went WILD,, as did the V-Twin market.. Thats probably why Yam upgraded to 1300cc,, or maybe it was a torque thing... Another thought,,, when you increase piston size you also increase piston weight.. Perhaps those engineers at Yamaha had some concerns over the added weight of 3 mm bigger pistons spinning up into the area that the Max needs to rev to do its thing.. I only say that because I know when Yamaha came out with the YZF's (dirt bikes and street) they had to go with pancake pistons to overcome piston destruction spinning up as high as they do.. Of course, when Honda came out with the CRF450 they had to follow suit.. These pistons are about 1/2 inch in height (thats about 12.5mm in your language) - not a lot of mass.. In the end though,, I honestly think it had all had more to do with the old "why change it when it is selling like hot cakes just like it is" routine.. The Max had that and is still today, a "cult" bike if you will. Notice how our Ventures really never caught on (well,, compared to Wings - at least around here anyway) and that Yamaha STILL hasnt come out with a new REAL Venture yet but did come out with a new V-Max? I happen to think that that is all about what I am talking about... Link to comment Share on other sites More sharing options...
WildBill1 Posted October 2, 2015 Share #6 Posted October 2, 2015 I need some more popcorn this is great reading guys love this stuff. Link to comment Share on other sites More sharing options...
Dano Posted October 2, 2015 Share #7 Posted October 2, 2015 I think I remember that "I knew/someone had told me" that the first 6 months of the Venture in '83, they ran like squealiin' pigs and they had to slow 'em down a bit...bit softer valve springs, carb flow, etc... I DO remember (not the feeling, tho) my '84 was a runner, could lift the front tire whenever I wanted and scrape the pegs off in turns,,,, Link to comment Share on other sites More sharing options...
Great White Posted October 2, 2015 Share #8 Posted October 2, 2015 I think I remember that "I knew/someone had told me" that the first 6 months of the Venture in '83, they ran like squealiin' pigs and they had to slow 'em down a bit...bit softer valve springs, carb flow, etc... I DO remember (not the feeling, tho) my '84 was a runner, could lift the front tire whenever I wanted and scrape the pegs off in turns,,,, My 83 is certainly "ok", but for sure doesn't "run like a squealing pig". But, after this winter it will have a VMax top end, a RSV transmission and a VMax final drive. Should be lots of "squealing" after that! http://www.ls1gto.com/forums/images/smilies/burnout.gif I'm even toying with the idea of a stage 7 kit and possibly a 4 into 1... http://www.smileysnetwork.com/fou/fou33.gif Link to comment Share on other sites More sharing options...
zagger Posted October 3, 2015 Share #9 Posted October 3, 2015 I added the V-boost but kept the '83 valves and drive train - runs good with the boost cracked open but I'm guessing that the rest of the experience depends on modifying the intake system. Let us know the details! zag Link to comment Share on other sites More sharing options...
Great White Posted October 3, 2015 Share #10 Posted October 3, 2015 (edited) ... Let us know the details! zag Who? Me? If you mean me, I won't know anything until next spring when it rolls out for the first time. No plans to add v-boost at this time, unless I find a manifold for a song. Then maybe... Edited October 3, 2015 by Great White Link to comment Share on other sites More sharing options...
slowrollwv Posted October 3, 2015 Share #11 Posted October 3, 2015 Sounds like the squealing may be coming from your wallet. Link to comment Share on other sites More sharing options...
Great White Posted October 3, 2015 Share #12 Posted October 3, 2015 Sounds like the squealing may be coming from your wallet. Nah, it's past squealing and just comatose now....http://www.scarletuser.com/images/smilies/svengo.gif Link to comment Share on other sites More sharing options...
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