ideas to make some POWER

[ap72]

here's the deal, I have a GS650 which I absolutly love! I would like some more power though. I'm looking for some ideas to add some serious power. I'm looking at getting a set of cams ground from WebCams along with some head work and a solid engine rebuild. After that then what? I assume I'll have to go turbo but what is a good turbo to go with? Is There any way I can run a turbo with out an electric fuel pump? I've built a LOT of high performance car engines (everything from a typical chevy 383 to a pontiac 2.5L and especially Olds 350's). I don't have a huge budget to blow so any way to do this relatively cheaply would be great. I can do almost all my machine work myself so machining is not an issue. Also, where is a good place to get some valve springs for this engine?

Oh, and it must remain streetable since I spend little time at the track.

[zig06]

Honestly, if your seriously talking about turbo's, cam's and what not. Your best bet is to just sell the bike and buy something newer. This is because even if you could double your HP, you would still be below what a stock '07 GSXR-750 pumps out. And for the money, it may even be cheaper to buy new when you factor in how much it's really going to cost.

I don't mean to be a buzz killer, I just want you to realize that your bike is 20 years old, and it's time is long past. The best that you can do is to enjoy your GS-650 for what it is. A nice bike that will cover many miles with out a complaint or asking much from you.

But for what it's worth: Modest power gains can be had with a pipe, but plan on rejetting to get that right. New tires and rebuilding the suspension will let you corner harder too. And by then you'll have max'ed out the design of that bike.

[Mark M]

+1 on what zig06 says. If you really want more speed, you need to buy a newer and/or bigger bike. If you want to keep a GS, look for an 81-82 1100E. If you simply want faster, anything fairly late model will do it. All you will do with your mods to the 650 is take a nice, easy riding street bike and turn it into a nasty running, troublesome bike that lost all of it's nice qualities and gained only a bit of straight line speed.

Mark

[chef1366]

BadBillyB has a drag bike he's selling. Leave the 650 alone. :-D

[Grandpa]

This kind of thread seems to occur quite often these days: People who want to turn their GS bikes into something they're not. More power? Simple solution(s):

1. Get a modern bike. A typical 600-cc modern bike produces a tremendous amount of power.

2. Get a large GS bike. Get yourself a GS1150E, or, if you want a shaftie, a GS1100G.

I agree with the responses to this thread. Turbo on an old GS650 -- ridiculous. :-D

One thing is to make modifications that will enhance the bike's already-decent performance, riding comfort, reliability, and longevity. We've all done that. Another thing is radically to change the character of the bike.

[rosco15]

1. First remove the 650 side emblem.
2. Secondly Replace rest of motorcycle with hayabusa.
3. Finally Put 650 emblem on side of hayabusa.
Presto 160 HP 650.....

[lecroy]

We have a local guy that has a Yamaha 650 twin that he races. This bike is very quick for what it is. He sprays nitrous and built a turbo system for it. The problem is the motor never seems to make it all the way through one race. It used to be the clutch would come out of it but now he has built a custom clutch using busa parts! All this to run in the 10's. Mind you it is not a street legal bike.

If your going to put a turbo on it, forget the cams.

We also had the kids RD bike running very close to the 10's. A lot of work.

The small motors have one advantage, they are light. If you go with a 2 stroke, even better.

That said, I agree with everyone else. If you want a reliable higher powered street bike just buy one.

[HiSPL]

I'm all for making power, but remember the shaft drive. If that blows up your kinda stuck. It's much more expensive to replace and you can't change gearing.

The easiest and safest thing to do is follow the exhaust>pods>jetting route. This'll wake up the engine nicely. Even if it doesn't release alot of HP, it'll feel faster simply because of the faster spinup of the engine and louder noise. If you want cams after that go ahead. Get some mild webcams and degree them in. That would be about all I would do to this engine/drivetrain combo for the most cost effective and reliable power.

Don't forget you can strip the bike of any excess weight. Light = fast....


Good luck!

\\/

[spyug]

As the others have said, don't waste time and money on the 650, it isn't going to make a tremendous difference in performance. What will help a bit is the suggestion to rejet the carbs and add a freer flowing exhaust coupled with shedding all excess weight.

I have an XS650 that has been rebuilt as a Street Tracker. The original bike came in at about 460 pounds and somewhere around 53 HP. The mods are too extensive to list but basically I took it down to the frame and tossed all parts that wouldn't be needed like rear metal fender, turn signals, front metal fender, stock seat, battery holder, stock mufflers, centerstand etc. and got the weight down to about 390 pounds. With rejetting, foam airfilters and freer flowing muffs got the Hp upto about 56. With some head work ( port and polish, vlaves and springs) I can likely get it to about 60/ 65. The bike moves quite nicely and is quite an improvement over stock especially with the suspension mods that were done but it is no match for the GS750. The 80+ horsies that bike makes feels like riding a rocket ship in comparison to the 650.

If you want a screamer get something newer, you won't be able to do it with any mods you can think to do on the old 650.

Sorry to be another wet blanket, just trying to save you some dough and driving yourself insane.

Cheers,
spyug.

[pickardracing]

1. First remove the 650 side emblem.
2. Secondly Replace rest of motorcycle with hayabusa.
3. Finally Put 650 emblem on side of hayabusa.
Presto 160 HP 650.....

Best post ever.

[raceman]

Do you love the bike? what a lot of people don`t understand is that gearheads like to build on what they already have,not just plop down some money like anybody can do. A guy buys a boat,fishing poles, Thousands of dollar$$ in gear,just to catch a $20- fish. You don`t tell that guy " hey,just save yourself the trouble and get a fish at the market,just buy one that`s already caught and cleaned". This is a PERFORMANCE MOD forum. True that older small bore bikes are less then ideal platforms to build upon but it`s the Journey that matters,it`s the build itself. These naysayers have a point but it`s mute since you want to hot rod the bike you have.l suggest NOS. You`ll need to get a pressurized fuel supply so you can inject both gas and NOX for a wet inject system. When that 650 motor gets tired l`ll sell you a good 78 GS1000 motor,engine swaps are the most economical way to add power to an old machine and for $150 you can have a good powerplant that triple your present horsepower level. That should sustain the need for speed:-D

[t3rmin]

If that's a 650E, he's got a chain, not a shaft. He didn't say which model...

[Hap Call]

There was a turbo built for the GS650 - the XN85. It was a production model that that was Suzuki's answer to the Turbo bike race in the early '80s. It put out a little more HP than a GS750E, but not much more. If you are set on a turbo you might look into this option, but remember you will have to lower compression and change the pistons to the XN85 pistons before you run the turbo - that is if you can find one, they're very rare.

http://www.xn85turbo.com/index.html

If you elect to go with laughing gas, I suggest you use a GS650 with a roller bearing bottom end to handle the increased HP. The GS650 came in more variation than any other GS engine - plain bearing or roller bearing, shaft drive or chain drive.

Overall, I'm with the other good folks in this thread - leave it as it is and get a newer bike or a GS1100/1150. The GS650 is a fine machine but it would be VERY expensive to modify and still be "streetable" but I do understand your gearhead side wanting to build it up. Now a cool option is to get a '80 or '81 GS1100E, pop off the side badges, and pop on some GS750E badges from the same year...Instant sleeper!

Hap

[lecroy]

I did not have a recent picture, but this is the 650 Yamaha with the turbo and N2O. It was a home made bike. Very cheap to build as the motor is stock. I'll try and remember to get a picture of his busa clutch on it the next time we are at the track.

You could go this route with a small car turbo. I forgot what he told me this one came from. Not a whole lot of fab work.

Raceman is right, there are guys that love to build this sort of thing up. But like I said, its a 10 second bike at best, when it makes it down the track. There is no way he could spent this amount of time on it unless he really loves doing it.

[bwringer]

We still have no idea what sort of 650 we're discussing here, but what's all this crap about straight line speed? Any numpty can twist a throttle.

Why not embrace the far more subtle and refined art of turning your bike into a handling demon, and yourself into a highly skilled rider?

First, install new fork springs, fine-tune the fork oil viscosity and set the right amount of sag using spacers (maybe $80 total and a couple of weekends of experimentation).

Next, bolt on some premium shocks ($200 and up for Progressive or Hagon, $350-$400 for Ikon, more if you want the full-zoot fully adjustable units.)

Somewhere in there, spoon on some premium modern sporty rubber -- Pirelli Sport Demons are the gold standard for GS handling. Maybe $220 a set, and you needed tires anyway, right? (The new Avon RoadRiders are also excellent, and a bit cheaper.)

You might also need to attend to the fork seals, swingarm bearings, and/or steering stem bearings along the way, none of which are very expensive.

Add in stainless steel brake lines and premium brake pads (anything but OEM).

Now here's the hard part: get the engine and carburetion back to bone stock (richen the idle mixture screws slightly), then LEAVE THE ENGINE ALONE. This means new o-rings for the carbs, seal the airbox, make sure the air filter is correct, and probably new engine/carb and carb/airbox intake boots. Set the float height very slightly rich, then fine-tune to achieve the smoothest possible transition from idle to 2,000 rpm.

You see, once the road begins to curve, Big Speed is not found at wide open throttle -- the secret is smoothness at low rpm, when you're just getting back into the throttle in a turn. The sooner and the smoother you can open the throttle, the faster you'll be. The amount of power matters only to goons who can only wobble through the turns then yank the wires open.

Of course, the final piece of the puzzle is you -- safely taking advantage of your bike's handling potential requires a high level of riding skill and committment to improving, maintaining and practicing that skill.

If you haven't already, take the MSF course, even if you've been riding for years. Listen, learn, and correct your bad habits to build the proper foundation.

Find some twisties and ride them as often as possible. Practice in parking lots. Program your brain with the angles when the peg drags on the right and the centerstand drags on the left. Ride with people who practice The Pace, not macho daredevils or pottering cruisers.
Article on riding The Pace: http://www.ridehsta.com/html/safety.htm

Attend a few GS rallies and tag along with the group up front. Don't try to keep up and ride over your head, but pay attention and learn firsthand what these old bikes are capable of in the right hands. Try to attend a track day or three if you can find one nearby that allows vintage bikes.

On a motorcycle, 99% of speed is the rider, and maybe 1% is the bike. Very few riders are willing to actively improve their skills, believing that they were born amazing and immortal. Take care of some of the basics on your bike and spend a few years improving your skills. You'll gain far more speed that way than by trying to turn a GS650 into a drag racer.

Plus, it's a lot more fun to watch the goobers on CBRs, GSXRs and Ninjas get smaller and disappear into your rear view mirrors when you're on an old, heavy, and "slow" bike.