88 Vmax 1200 "Bobby"

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one2dmax

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Took her out onto the main road, and ho-lee shit. I can't believe I thought I was running on full power before, this is not even close to the same bike. When the vboost opens, the whole bike squats back and the acceleration is immense. I definitely need to look into upgrading the suspension. It was honestly scary to ride as it is now, I had a hard time keeping it on WOT because it felt so unstable. I owned a gsxr thousand for a year, and that bike was probably faster on paper, but the rush of torque and the sound from this bike is impressive and exhilarating. I took it to my friends shop down the block, and him and his buddy agreed this bike was way faster than they expected. Last time I brought it around, I got some laughs because of the general condition of the bike and its age, but now they both want one for a project 😁
Wait until you replace the Cobras with a full header and gain 20% more power in an instant.
 

kwikrider

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You want to gain security in the operation of the bike, I suggest switching to radial tires is in my experience the #1 best change you can make. You need to replace the rear wheel at a minimum, to either a 17" (better acceleration as it's not as-tall as-stock, so it's effectively like gearing it lower/higher numerically) or 18" (not as-much of a 'gearing change,' as it's taller overall, and you still maintain your top speed, but how-often do you go 150 mph?) . You can add a radial front tire to the OEM wheel, but it's at-least an inch too-narrow for the radial tire to take the proper 'squat' on the rim, where its wider profile maximizes handling. If you do choose to just add a front radial tire to the OEM rim, do-not oversize it larger than stock width! Doing that further compromises the spread in width of the radial tire on the OEM rim, you don't want that.
I just bought Dunlops, I thought all modern tires were radial. Is it possible I have bias plys on there? I just compared the tires to the ones on my 98 bandit 1200 and they definitely have a larger sidewall on the Vmax. I noticed driving it on a grooved concrete highway near work that the tires definitely pull the bike more than I'm used to.

Diagnosed the bad stator today and pulled off the cover to inspect it. Not sure how to confirm the failure on the bench, but I was getting low and intermittent ACV on the three wires to the rectifier, which I was told points to a bad stator. The wiring definitely looked original. Found a good deal on a new unit on eBay, that will be coming in the next few days. Really looking forward to getting to know this bike better on the road.
 

kwikrider

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Wait until you replace the Cobras with a full header and gain 20% more power in an instant.
That's alright, I'm not sure more power is what I need at the moment 😁 I do also like the sound from the pipes, and having an outlet for each cylinder makes tracing faults a little easier.
 

Fire-medic

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That's alright, I'm not sure more power is what I need at the moment 😁 I do also like the sound from the pipes, and having an outlet for each cylinder makes tracing faults a little easier.
OMG, 😫😳 OK, your choice!

A stock VMax with OEM exhaust and jetting does well on the street. Sure, a current 600cc sportbike can best it in a test of acceleration, if it's ridden by an experienced rider, running it to 15,000 rpm, or whatever they turn these days. But the displacement and VBoost mean that the VMax, running at say, 5000 rpm, and then having the throttle wacked-open, hitting VBoost, and shifting through the gears, by the time you're in triple-digit bike-impoundment/license suspension territory, the stock bike, not-hampered by performance-reducing mods, will be doing very-well against most 2 or 4-wheeled competitors.

I admit, the Cobras are purty, in a Deliverance sort-of way.
I run 'em mostly-stock, as the bike acquits itself well against the competition, but my choice would be to swap-out a set of Cobras for someone who values looks over performance, and to return the bike to at-least OEM equipment/specs, to enjoy the design parameters set for the bike from the factory. It's much more-fun than having the lessened power output and soggy throttle response of a Cobra 4-into-4 system. There are always guys out-there who like the Cobras for looks, but as a famous movie character once said (paraphrase), "I just gotta-go, man!"
 
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kwikrider

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It would be interesting to drive a bike with the original system, from my perspective the throttle response has gotten much better as I've dealt with issues, but still not inline 4 sport bike zippy like my bandit.
 

Fire-medic

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I've ridden two Cobra equipped bikes for sale locally, at the request of prospective purchasers. Both had worse-than stock throttle response, and let's just say, VBoost was as-impressive as a clown at a funeral.

I understand that for some owners, their appearance is 'cool,' but the performance compromise they cost on the one remaining Japanese muscle-bike is more-than I can bear, if it was in my fleet. I'd rather run a scabbed-up OEM exhaust than a perfect Cobra. If I ever-bought a bike with a Cobra, that ride would be getting a Cobra amputation as-soon as it got-home. I already have the scabbed-up OEM system, waiting. ;)

Few carbureted bikes are going to come-close to a production fuel-injected motorcycle for throttle response especially if you're going from the valley into the mountains, with thousands of feet of elevation change, then probably no carbureted bike can compare.
 
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kwikrider

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vboost certainly impressed me on this setup, but I'd certainly entertain trying the stock setup if its as good as you say, and its available cheap and local. I think fixing the soggy suspension is more of a priority now.
 

Fire-medic

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vboost certainly impressed me on this setup, but I'd certainly entertain trying the stock setup if its as good as you say, and its available cheap and local. I think fixing the soggy suspension is more of a priority now.
There's a Gen II exhaust system by you, on CL, but that doesn't help. There is a stock Gen I front wheel/tire for $35, if you want to widen your front wheel, there's a donor rim. No brake rotors, claims the tire has 150 miles. 1993 Vmax front wheel with tire - motorcycle parts - by owner -... (craigslist.org) in Santa Rosa. Check the date code on the tire, to confirm its manufacture date. $35 is probably what a H-D shop would charge you to change a front tire. If your front tire is worn, depending upon the brand, this might be an inexpensive way to get a replacement front tire. I like to use the same type of f & r tires, same manufacturer, and same series. With radial tires, that's especially important as the method of construction can affect your handling if you mix different design methods, and not in a good way.

If "VBoost certainly impressed me" with the Cobra exhaust, then getting something-else like a stock exhaust system, or another aftermarket system which doesn't cause a big-power loss will have you feeling like this character actor. It's gonna-be a M____ !

Mindblower speakers.png

Put it this way: guys will spend $1,000+ for someone to install a jet kit and a new aftermarket full-exhaust onto their bikes, and to tune it, and get less of an improvement in HP gains than you could easily-get by re-installing a completely-stock exhaust system! That's a M_____!

Mindblower speakers.png
 
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Fire-medic

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I suspect all you need is the megaphone. Pretty-sure the Cobra 4 into 4 is a slip-on, using OEM header pipes F & R. I probably have a scabby old megaphone set you could slap some black high-temperature paint onto, to get you your lost horsepower back.
 

norcalAF

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I'm happy to see another bay area Vmax Rider! I put some supertrapps I scored cheap from ebay on mine, and immediately pissed off my wife and neighbors!
 

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