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I found a thread titled "Everything you wanted to know about cam swap" but I didn't see anything in the post. It appeared blank.

I have a 10 round clip of questions on full auto.

Premiss: I have a previously modded 2002 SV650 so I don't know what cams or jets are in it now. I can see it has K&N air pods.

1) How much power increase can be realized by installing 2nd gen cams in 1st gen motor?
2) Should I install 4 2nd gen intakes or stock set of intake/exhaust 2nd gen cams?
3A) Are different jets required?
3B) If so, what size? How can I tell what size the ones in there are?
3C) If so, which jet(s) do I replace?
4) in case it already has swapped cams, how can I identify 1st gen from 2nd gen? I'll share what I have learned: 1st gen have letters A, B, C, D stamped close to center on sprocket side and 2nd gen are F, G, H, J.
5) can I use the same timing marks and install the 2nd gen cams like the factory manual shows or is it different?
Okay, that's only 7 questions but answers sometime lead to more questions.
 

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2) the most popular is 2nd gen intakes on intake, 1st gen intakes on exhaust

3A) maybe, mine was pretty good with the jetting I already had
3B) jets are generally labeled with a size (there should be a symbol too, to tell you type of jet)
3C) mains if anything, maybe needle height too

4) I'm having trouble finding that. I believe the cam itself should have a letter on it, but I don't recall what letters correspond to what.

5) if you're just swapping in 2nd gen cams, I believe you can use factory marks. If you're using 1st gen intake cams on the exhaust, you'll need to set them differently. http://www.bayarearidersforum.com/forums/showthread.php?t=154847 has some info but all the pics are gone.
 

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Discussion Starter #3
Thank you for the reply. I've been looking and asking around and was beginning to think it was a secret.

"3C) mains if anything, maybe needle height too"

By "needle height" do you mean float valve needles? I just serviced the carbs and the floats are just under 7mm. factory spec is supposed to be between 7mm - 0.5mm
I'm not sure why they call it a needle. It's really more of a rubber cone.
 

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1. depends on who you're listening to, i've seen claims ranging from 3 to 7hp with strong gains on the low end and midrange.

3. Some people claim you can get by with factory jetting, I don't buy it. Jetting is dependent on all kinds of factors. No one will be able to give you a solid answer. Be prepared to pull off the carbs a bunch of times dialing in the tuning or to fork out the money for dyno tuning.

4. It'll be fairly easy to see if the swap is already done once you pull the valve covers. If you rotate the motor to the "f" mark on the flywheel like the manual says and only the intake cams alignment marks are correct and the exhaust cams marks are way off, then it's probably already been done.
 

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regarding jetting, needle height means the height of the needle in the slide.

maybe a different needle would help too, but height is very easy to adjust.


frank, bigger cams tend to help more up top than down low.
 

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frank, bigger cams tend to help more up top than down low.
Bigger cams typically help up top with more duration. Pretty sure the 2nd gen cams are the same specs just with a little more lift. I'm not a SV engine guru, so I don't know this for sure, but it's likely there is a limiting factor to flow at the top end of the rpm range (heads, exhaust, intake). If that's the case higher lift cams could very easily give bigger gains at the bottom and midrange. Then again, I could be wrong and just be blowing smoke out of my ass. I'm just going by what I noticed when I did the swap a month or so ago.
 

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I didn't find the thread either, I was hoping it would be a "sticky"... as it's an important gain foresure....

although, I find that the "cam swap" (larger 2nd gen intake and larger 1st gen intake moved to the exhaust side) steals a bit of down low power and makes for an overall slower revving engine.... (I know people will question this observation) but, I was thinking of trying just the larger intake cam from the 2nd gen and leaving the stock (small) 1st gen exhaust in place to reduce "overlap" (as it robs power down low)... anybody tried that one? I may try soon...

currently I'm running both 1st gen intake cams (both sides, intake and exhaust) which gives really good mid range boost in power but lacks the power up top near red line.

My other idea is that with the 2nd gen cam swap the stock carburetors are just too small to take advantage of the top end power boost (this again is derived from my current "same" intake + intake cam configuration... feeling it's better than the "cam swap").

what I've noticed is that the stock cam configuration gives peak power at about 9k rpm... the "cam swap" configuration gives peak power at 10k rpm... and the dual 1st gen intake cam configuration (I am running) gives peak power at 9.5k rpm.

I'm hoping that using only the intake side cam of the 2nd gen (fuel injected) engine will then give me the 10k peak power and no disadvantage of poor revving up in the low/mid range (as I hear that most engines are "over exhausted")...

all of the cams have differences in both lift and duration when changing between them
 

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here is a link to some photos I've used for doing the "cam swap", changing between intake and exhaust cams (moving intake cams over to the exhaust side of the engine), borrowed from another forum years ago.

https://photos.app.goo.gl/nDvsfeDQ9Ymksf578
 

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... I just got around to trying the "other" cam swap config. I have on offer over here... putting the bigger 2nd gen. intake cam in with the stock (1st gen.) small exhaust cam... and so far so good... the engine seems to rev faster - but the peak power seems a little lacking right now... cutting out around 9k rpm...
to each his own... I'll be testing this config. more
but so far I've noticed much better acceleration off of corners in higher gears (4th, 5th, 6th), smoother idling, quieter exhaust noise,
engine seems to respond to throttle inputs much faster and with more power (better connection to the right wrist)
some maybe's: better fuel economy, faster (these yet to be fully confirmed)

(other tuning considerations: I'm running K&N air filter, stage 1 jet kit, Akra full exhaust with free flowing "race" baffle muffler)

now, sure there are other cam configs. I can try... getting the 2nd gen. exhaust cam comes to mind... as does getting the resources to adjust the cam timing... but, that's just out of my reach right now...

of the three configs. I've now tried... I think the current one so far feels the best (compromise)... shall I say it... compromise...

... update 2/25/2020: "this" config. makes for a meaty mid range engine... I'm keeping it for now... engine definitely lost the top end punch. I played with carb. jetting a bit and not seeing a return of losses at peak rpm...

this configuration seems to make for a better engine in the twisties but poorer performance as a drag racer...
 
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