New to Vmax

[fierslow]

I have always wanted one of these bikes and recently found this 95 on craigslist for 2500 and could not resist. After buying it I noticed the stator cover said "yamaha 1300". Sure enough after finding the engine code, 1NL-000667, and after referring to some threads on this site I now realize that this is not the original engine for the bike. I believe it is a Venture block with all the Vmax goodies on top. I do have a few questions though. Is there any advantages/disadvantages to this set up? I would assume the old saying "there is no replacement for displacement" would hold true, but I don't know if this setup makes for lower compression etc.. The bike fires right up and idles smooth, and seems to run very strong from what I can tell. Honestly, this thing scares the crap out of me, being that it is my first street bike. Anyway, i'm glad this forum is here and has already helped me out greatly. I would appreciate any answers to my question. Thanks again for having a great forum for Vmax owners!

Donny, Tulsa OK

 

[maxcruiser]

Welcome the forum and it looks like you have a unique max on your hands. Bike looks in great condition.

The Venture 1300 engine conversion has been done with great success, because as you stated, there's no replacement for displacement! From the pictures, your bike seems to have the original Venture heads, rather than Vmax heads. Usually, the 1300 conversion is done using the Vmax heads. Do you know any background on the bike from the previous owner?

Mike

 

[fierslow]

Unfortunately I do not have any background information on it, I was going to contact the person I bought it from tomorrow to see if he knows anything else about it. I'm not sure what he will be able to tell me though as he only owned the bike for two years, but there is a slim chance that he may be able to provide me with contact information for the original owner. He did tell me that when he posted it for sale the original owner did contact him to see if it was his old bike so he might still have that info. Just out of curiosity, how can you tell the difference between the heads? I did get some casting numbers off the heads and was trying to find a way to look up information on them.

 

[maxcruiser]

The easiest way to tell, is the difference in the cylinder side covers (X4). The ones one the Venture Heads are about 4" long and the vmax ones are about 2.5" long. Also the Vmax head have 3 "fins" and the Venture one's don't.

I included a pic of the Vmax heads up close, so you can compare yours to them.

Mike

 

[Jdk203]

Looks like you found a pretty sweet deal. Welcome to the forum and enjoy the bike.

 

[CaptainKyle]

Welcome to the forum ! have fun with the new bike

 

[one2dmax]

that's a normal 1300 in the bike right now. A regular vmax 1200 will pretty much put the whooping on you. You need to change out the heads and cams to vmax parts and it will take care of that - add about 20-30 hp and make it stronger then a vmax. Then get rid of the 4-4 Cobra slipons and you will have a whole new beast!

Basically between the exhaust and venture heads you are down 30% on power. I would not say this was a supreme find just because of the bigger engine. You got a good baseline to start but got screwed out of the most important parts you needed that makes all the power.

Sean

 

[gamorg02]

isn't another question, what happened to the vmax engine?

 

[Jdk203]

isn't another question, what happened to the vmax engine?

Its in the previous owners venture ; )

 

[PATMAX]

$2,500 for a 95 that runs good with a stock 1300 Venture motor? I'd be cool with and not feel a bit taken. Like Sean said, you have the foundation for a sweet upgrade. Heads are easy to come by. Sean does the Vmax/Venture conversion in his sleep and one of his regular offerings.
Welcome to the Forum. It is supported on a donation basis so if you feel it is worth keeping around, consider a contribution. Personally, I can tell you this site has saved me money and earned me some money. It is a treasure trove of info, experience, parts and some good people. Have fun with that thing. You may not have VBoost on there but you are no longer a stranger after your first blast of Boost! Welcome from the fat Filipino, PATMAX

 

[RaWarrior]

While it's definitely down on power compared to a regular Max, as I'm sure you've noticed it's far from a scooter. You're probably still putting 80-90hp to the tire, which is nothing to sneeze at and will easily shove it to 120+mph.

Since you said it's your first street bike, maybe give it a year or a few thousand miles or so to get used to what you already have before hopping it up even more. My first street bike was a 22 horsepower GS450.....so you're already way ahead of the curve in my book.

"no replacement for displacement" is getting to be kind of an old phrase, it's not nearly as true as it used to be. A high-tech turbo four from Japan can/will outperform big, lazy American v8's with triple the displacement, and weigh less, and get better economy. It's never been particularly true with bikes either. Your Yamaha 12/1300 will put the hurt on a Harley with 50% more displacement. It's using the displacement more efficiently. You could say the engine works smarter instead of harder.

 

[fierslow]

Well thank you everyone for the information. Will the Vboost still be functional with the Venture heads? I am not too worried about making it any faster right now. I need to get used to the weight and feel of the bike first, like a said before it already scared me a little so I am not too concerned with adding the 20 - 30 hp right now. I also see that vmax heads are found pretty easily and reasonably priced on ebay, so I may go ahead and get a pair of them to start working on.

 

[Saml01]

How is the venture head different than the vmax head?>

 

[RaWarrior]

I'm fairly sure your motor doesn't have v-boost. You'd have to get Max manifolds, the v-boost mechanism, and wire in the controller(or use an aftermarket like a SASY). I suspect the carbs would need rejetting/adjustment if boost was added also.

Vmax heads run higher compression and have "hotter" cams than the Venture. There may be other differences but those are the two biggest factors.

 

[one2dmax]

The v-boost is usually on the chassis and when i've seen the same situation on other vmax's they usually still have it (listen when you turn the key and see if it at least still cycles - then you can visually look at the intakes - the venture were rubber and the vmax are aluminum).

The venture engine before swapping the heads over is typically cheaper then a good vmax engine and why some swap them over. Some think they are a bolt in jump in power which is not the case if the other parts are used.

The compression is actually the same (10.5:1). The venture valves are heavier and cams are significantly smaller. So, less rpm capability. The rods are heavier too but we've not found that to be an issue. The pistons are also heavier (longer skirts) though this too hasn't seemed to be the weak link. In fact, the flat top of the venture pistons is better for flame travel (better combustion).

There are pics comparing the venture parts (at least some of them) to the vmax on our facebook site. You can't just use the vmax valves in the venture heads without a shit ton of work (all new guides and valves at a minimum).

The trans is also a little different and uses a design similar to the recall 85 vmax transmissions. We haven;'t really had a lot of trouble with these either but anytime we do a trans job we go ahead and upgrade the 2 needed gears while we are at it (2nd and 5th).

The venture head is easily recognized by the lack of fins. Once the vmax heads are installed then it's virtually impossible to tell it's not a stock vmax block. Only the engine vin and cc casting (under the front head between the exhaust pipes) can give it away.

You would be very surprised at how much we are talking you have lost in potential for the bike. As noted you can start gathering the parts up to make it the beast it should be.

Sean

 

[fierslow]

Well it does appear to have the carbs and intake with the vboost mechanism, what wiring can I look for to see if it is hooked up?

 

[one2dmax]

Black box under the left scoop. Approx 3" x 3" x 3/4" thick. Right side. Has a round 5 pin plug in and 3 wire rect plug in. The round pin goes out to the servo motor mounted under the support bracket for the front coils and CDI box. From there you have a cable running from the servo down to the linkage between the front and rear carbs. When you turn the key on this system runs a test and actuates that linkage open and closed. Easiest to see that movement from the right side of the bike.

 

[Saml01]

Venture to Vmax block, is it a difference in bore or stroke?

 

[one2dmax]

Same crank specs, different bore 76mm vs 79mm

 

[gamorg02]

sean, why do you think in 85 (actually probably decided sooner) they went with the 1198 engine? why not use some different parts and do a 1300 engine which would be more powerful, stock?