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Discussion Starter #1
PLEASE READ BEFORE YOU VOTE  :) --- Correction: 15T should read 16T in the poll ----

Well... I kept telling myself that I wouldn't change the gearing because I liked the way the 15/44 I have on it now acts in the twisties... BUT, I keep getting this bug, you know... the speed bug.
I found out the other day that I can bounce the thing off the rev limiter going up hill (I was passing a group of RSXs at the time)... and its not like it just barley gets there either so that got me thinking... and thats usually a bad thing  :D
So according to the SV Gearing calculator that someone posted on here a while ago, with a 180/55 17, and 15/44 gears... the actual speed Im seeing should be 148.4 mph. Not bad, but how much more does it have?

+1 in the front gives me up to 158.3mph
-1 in the rear gives me 151.9mph
-2 in the rear gives me 155.5mph
-3 in the rear gives me 159.3mph

So im askin you guys... Should I go one up on the front or down some in the rear? Or should I just leave it alone and enjoy being able to smash the rev limiter in 6th?

This chain and sprockt only has about 700 miles on it atm so either sprocket can be changed without a problem.

Should I change it or am I just crazy? :eek: What do you guys think?
 

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if you want to go faster, get a liter bike. i think that is fast on an SV. Hell, what do I know, I just sold my R1 and drive a supercharged lifted 4runner
 

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Discussion Starter #3
FilthyRich said:
if you want to go faster, get a liter bike.
Lol, going fast not the point... SV is not that fast, have a few other things I could use if I wanted to go fast (bandit 1200, busa). Seeing what the bike would do, that is more the focus. I just don't know if its worth it. Would drop gear ratio, would have to slip clutch more off the start... might get better mileage etc...I dunno :-\

I never post mods before I do them so I thought I would post this one and ask what you guys thought  :)
 

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I think you first have to explain how you got the motor to produce enough horsepower to go 148.4 actual mph up hill :eek:
 

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Marc said:
I think you first have to explain how you got the motor to produce enough horsepower to go 148.4 actual mph up hill  :eek:
I second that, considering I have full yosh system, stage 3 jet kit, and stock gearing, it's hard to hit 130, let alone 148.4....
 

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with a stock motor you're not going to get any higher top speed with just gearing. You may actually get a higher top speed with a higher ratio.

Can a stock SV really do 150MPH? That seems just a little high to me.
 

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Discussion Starter #7
Read my sig guys. Theres more crap on there than I care to remember  :D

Full faring = better aerodynamics
Cam swap with Yosh cams (from race bike that got smashed)
Full D&D system w/ exhaust wrap
520 chain (mostly because of the GSXR rear wheel)

But the big huge difference was the custom intake for ram air. Which required me to use O2 sensors in the exhaust to get the mixture right. Which in turn means that I have the exact mixture that I want... Ive rejetted the thing so many times I replaced most of the screws in the carbs (stock carbs btw), some twice  :eek: I did ram air before cams and exhaust wrap. The wrap helped a little but the cams made things really interesting at higher rpm  :).
I did a big write up on it a while back, a few people were interested but there was too much involved for most people.

Feel free to read Sport Rider's opinion:
http://www.sportrider.com/tech/146_9910_ram/ Part 1
http://www.sportrider.com/tech/146_9912_ram/ Part 2

I use a custom set up thats totally sealed, so I get no loss from leaks (be sure to note which bikes have leaks in the article vs the results).

Those speeds are calculated based on the SV gearing calculator, my speedo is not working atm but I already know that I can peg it at an indicated 150 with a 120/65 17 on the front (larger series tire means less spedo error, but there is still some apparently).

So back to the question: Do you think I should change gearing to try and top it out?  If you dont beleive me, thats fine... just dont vote :) Someone neg reped me... I guess I will confirm next run with GPS and take picture :p
 

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Hot damn... you'z gots the Powa!! ;D

Yes, I think you could probably get more top speed with more gearing.
Assuming you have the stock front sprocket now, wouldn't it be most economical to get a 16 tooth front...

Can you hit the rev limiter in 6th?
 

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Discussion Starter #9
donniej said:
Yes, I think you could probably get more top speed with more gearing.
Assuming you have the stock front sprocket now, wouldn't it be most economical to get a 16 tooth front...

Can you hit the rev limiter in 6th?
Doh! I ment to make it a 16T front in the poll. I have 15T now.
If you read first post, I can bounce it off the limiter in 6th going up hill, which is what started this whole thing. I was passing about 8-9 Acura RSXs, they were doing ~100-110 and I didnt like being behind them, so I went around... and in the process I hit the limiter pretty quickly, got confused (cause I thought I was already in 6th) and went to shift up and found out I was already in 6th... and that got me thinking lol  :)

I dont top the bike out much but I thought it might be kinda fun to change the gearing and see how fast I can get it... so I threw up a poll  ;D
 

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Discussion Starter #11
ronlarimer said:
What would an O2 sensor do on a Carb'd bike?
Wouldnt do much good on any bike unless you hooked it to an A/F gauge. Note the little black box thing above the tach. Thats a Split Second A/F Gauge. I have a sensor in each header which gives me a reading of what each cylinder is doing. Had a friend of mine weld in fittings to the headers... the switches on the right side just below the idiot lights are what let me read each cylinder seperate, I switch back and forth between them. As they sit in the pic, they are reading the rear cylinder.



On a side note, you see the flexable metal hose just inside the faring? Thats the ram air ducts, they go straight into the air box from there.
 

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I guess I am still lost on the point of them. Without a ECU that adjusts fuel based on the O2 sensors you have a carb'd bike and the O2 sensors are irrelivant to everything. You would need to be pushing about 100 hp to hit that on flat ground wouldn't you?
 

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Discussion Starter #13
The ram air changes the mixture as you speed up... see the article, pressure in the air box increases (usually) as your speed increases so the amount of air the motor is getting changes. All that means is that if I jetted it on a static dyno and then just ran out there with the ram air the bike would die because its running so lean... and yes, that actually happends, Ive done it.

The O2 sensors dont work like a car, its not connected to the ECU and it doesnt change the mixture... I never needed to do that. What I did need was a way to measure my mixture while I was going down the road, so that I would know if the bike was rich or lean and then I could rejet it based on the readings.

Did you vote? :p ;D
 

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Adding 1 tooth up front = about 3 less in the rear = about 1000 rpm drop at 10,500, if that helps you in any way. That's what i would do if it's hitting the rev limiter easily.
 

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I find these speeds very hard to believe, but more power to you if you can do it!

You are using a wideband O2 sensor, I take it? And tuning for what? 12:1 dead on?


You are my nemesis, I am using a 14/47 sprocket combo!
 

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Discussion Starter #16
rwheelz said:
I find these speeds very hard to believe, but more power to you if you can do it!

You are using a wideband O2 sensor, I take it? And tuning for what? 12:1 dead on?


You are my nemesis, I am using a 14/47 sprocket combo!
Nope, wideband is for a car man. Its output range is 0-5V. The ones Im using are simple single wire output is 0-1V. All they do is give me a reading on the gauge, they dont control anything.

I tune it for 13:1 - 13.5:1.

As for beleiving me... like I said I guess I have to take pictures of GPS output next time. Or you can just come to Texas and ride with me :)
 

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lowering the gear ratio will not help your top speed,

the SV don't have enuf HP to overcome wind resistance, it's more likely to hurt you top speed, it will lower your revs at top for sure, but it is unlikey to make more than a mph or 2 difference
 

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I uise 16T front and stocke size rear and itworks great, wheelies are a breeze throttle only in frist still, and more relaxed cruising on highway, I use it at the track too, you won't notice any increase in clutch slippage to get away from a light, it's a completely natural transition from one to the other. Love it!
 
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