FINALLY! Got my bike dynoed...

[northwind]

For about the last year and a half I've been just about to get my bike dynoed, it's been absolutely ridiculous. I had it booked in then fractured my hip, booked in then crashed, booked in then had a cam chain tensioner go bad... So I've been riding around for about 2 years with nothing but my finely calibrated bum as a guide...

And it's not as bad as you'd expect ;) Fairly rich at idle, which I suspected, a bit lean at peak, which I'm a little surprised by... Just a hint lean in the midrange, but I think even a half-step on the needles will take it too far the other way, so that'll stay as it is for now. So down a quarter turn on the pilots, leave the needles, and up to 175 mains and that'll hopefully be it. I'll get the mains sorted then maybe play with the needles next time I've over.

Didn't do a proper power run, since the fuelling was the goal today, but on the one straight run it showed 77.13bhp at the rear wheel, not bad for a home-made bike :) "Fix the mains, and bring it back on a cold day, and it'll crack 80" says the boss. Usual dyno accuracy disclaimer applies...

[haggis]

Pretty ferkin' healthy my friend. =D>

[chunkytfg]

Usual dyno accuracy disclaimer applies...

your not kidding are you :shock:

[weazelz]

Didn't do a proper power run, since the fuelling was the goal today, but on the one straight run it showed 77.13bhp at the rear wheel, not bad for a home-made bike :) "Fix the mains, and bring it back on a cold day, and it'll crack 80" says the boss. Usual dyno accuracy disclaimer applies...

what mods do you have to take it up to this power level?

[northwind]

what mods do you have to take it up to this power level?

What'll count most is probably the cams- K3 intakes, and the stock intakes moved to the exhaust, nice cheap boost for £130. The exhaust and Race RS filter, combined with big jets, will do the rest. The slightly inept setup and hot humid conditions would knock it down a bit. And then the dyno adds or subtracts a few hp at random. There's a couple of other factors... Platnium sparks may or may not help, ignition advancer helps further down but probably does nothing on top. Compression and capacity is standard for now.

It's a fairly nice curve all over though, loses pace at about 4500 but no dips till right at the top, where the jets would cause it some issues. Reasonably pleased, it's nowhere near optimised but then that means spending money to chase tenths of a bhp, this is a streetbike so why bother?

[northwind]

your not kidding are you :shock:

Well, you know as well as I do how much they can vary from day to day... YPE's dyno's not known for generosity, since it's mainly used for pro work not "How much does it do, mister" but it's not been calibrated for a couple of months. Plus, the fact that they weren't shooting for peak power makes the figure less useful too. I'm not sure which model it is, think it's a 200.

So, yep, could be 75, could be 80, it's all luck of the draw. But for cams, full system, and good breathing it's a middle-of-the-road figure, so I doubt it's drastically far off.

[Sid Squid]

...a bit lean at peak, which I'm a little surprised by...
Don't be, ever so slight lean-ness often feels good - it gives a crispness in the fuelling and thus often makes it seem better. No substitute for a dyno set-up though, best way to make it quite right.

...ignition advancer helps further down but probably does nothing on topAgreed.

So, yep, could be 75, could be 80, it's all luck of the draw.Very true.

[Speedy]

Well done Northy!

Whats nice is that YOU did the mods,not someone else! :wink:

I'd be pleased!

[Saint Matt]

Nice one mate, comfortable 10 brake on top of mine :)

[northwind]

...a bit lean at peak, which I'm a little surprised by...
Don't be, ever so slight lean-ness often feels good - it gives a crispness in the fuelling and thus often makes it seem better. No substitute for a dyno set-up though, best way to make it quite right.


Yup, that makes sense. The plan was never to wing it for 2 years ;) It's close enough that youngs were surprised it hadn't been run before (they rather unkindly suggested it had been set up by a competitor ;) ) but no cigar.

[fizzwheel]

is standard for now.

this is the most important point in this whole thread.

:D

[northwind]

this is the most important point in this whole thread.

I'm not very comfortable with the S word :) But I picked up an ingredient today which might go into a new dish later on this year...

[svrash]

Right.........i want to know every thing carbwise, needle height, jets and sizes, turns........the lot :lol:

Good result mate :wink:

What next on the agenda or are you keeping it a secret (busa pistons??? inter coolers :lol: :lol: turbo/NOS :shock: :shock: :idea: )

[johnnyrod]

Re. ignition advancer, here is a trace of my bike before and after at JHS - had Akro system but no carb mods. Lots of bottom end, but a little at the top too.

http://www.johnnyrod.co.uk/dyno.gif

I needed a DJ kit to sort out the midrange, and have a little rich spot around 6-7k on full throttle which may or may not be helped by adjusting the needle. Once done there were no dips, so you should be able to smooth it all out. Post us a pic then! And give us a clue for the new thing...

[21QUEST]

Very healthy indeed :thumbsup: .

Almost as much as my professionally setup K1 was making(79 and a bit at the rear). Good thing I did pay for the work myself . I'll post my printout if I can find it.


Cheers
Ben

[1world2wheels]

Just wondering what standard Sv's are supposed to make? Is all the tuning worth the effort/exspense for road use?

[svrash]

Is all the tuning worth the effort/exspense for road use?

No :lol: .............but i do it for the love :wink:

[Law]

Just wondering what standard Sv's are supposed to make? Is all the tuning worth the effort/exspense for road use?

69-70 bhp standard if you trust the magazines.

[socommk23]

69.78bhp on my sv650 02. pipe and filter.

[PeterM]

By going up with the mains you may have fixed the midrange and have no need to adjust the needles. Obviously if the needles are pulling through larger mains then more fuel will be drawn at any given height.

Always best to get the mains correct and then adjust from there. Good work too, virtually the same as mine which shouldn't be surprising really as apart from pipes we have done almost identical mods. (my jets are Mikuni so not sure off top of head where relate to DJ ones)

[northwind]

Just back from the Soho Massive mmet on friday night- takes a litle longer to get back to Edinburgh ;)

Right.........i want to know every thing carbwise, needle height, jets and sizes, turns........the lot :lol:

What next on the agenda or are you keeping it a secret (busa pistons??? inter coolers :lol: :lol: turbo/NOS :shock: :shock: :idea: )

I've got 2 options here. I could pretend that the setup I have is a trade secret... Or I could admit I have no idea what the mix screws and needles are like ;) Jets are 170s for sure, and I suspect that the needles (DJs) are on the third clip, mix screws are 2 3/4. I thought I'd taken the screws back into 2.5 turns but that shouldn't really run as rich as it does, so perhaps not.

What's next? I just picked up a very cheap crank, since there's not many out there, so I might rebuild the nicer of the two blown engines I have. That'll keep me busy, assuming I can do it. If not, I'll put Busa pistons in my current engine, just for the project, but if I can get the other one up and fit then that gives me some interesting options :)

Ignition Advancer stuff

The concensus seems to be that the advancer'll add top end to a fairly standard engine, but on an even marginally tuned one retard actually gets you more peak power. Whether mine is that far, I don't know, but even if it were costing me a couple of bhp at peak I'd keep it, since the midrange boost is worth more to me. I like the ignition advancer :)

Is all the tuning worth the effort/exspense for road use?

Nope :) I enjoy doing it as an end as well as a means, but if not, for street use it's broadly not worth doing IMO. Better put the money towards a bigger bike if you want more power. Having said that, for me an SV with good suspension doesn't really have an "out of the box" equivalent, and it fits what I want from a bike close to perfectly. If I could go out and buy one, I would do, but there's not one to buy so I built one.

It's a slippery slope. The ignition advancer's a good and reasonably DIY-able mod at the price, for example, I'd do it and recommend it for anyone. Exhaust work? I'd say not, even if it's done as cheap as poss it's not very rewarding. Cams are better for the SV, but are they worth doing? Up to you. If it keeps the itch away and means you keep the bike for another year, then a couple of hundred quid's worth of tuning could be a bargain, especially when it's resellable bits.

As to power... Suzuki claim 72 at the crank for a K6, I think. Crank figures are another way of saying "we made it up" though. The closest thing I have to a stock figure with mine was 69.4 with a CCC pipe and Renegade airkit, on the same dyno as this run was done- but remember the Random Dyno Factor. I've always considered that number optimistic, and it was too long ago to really be useful for an honest comparison.

By going up with the mains you may have fixed the midrange and have no need to adjust the needles. Obviously if the needles are pulling through larger mains then more fuel will be drawn at any given height.


Yup, that's the assumption I'm going on too- might run it twice with a half-step change, just to check. I want to try it with my desnorkelled stock filter too, so I might book out a little time on a quiet afternoon.

[svrash]

If I could go out and buy one, I would do, but there's not one to buy, so I built one.

Spoken like a poet :lol:

[johnnyrod]

If I get the time at the weekend I can figure out my settings by looking in the DJ kit box and seeing which bits are left over.

[northwind]

:shock: Just opened it up and it's already got the 175 jets in there... Didn't think I'd be going up to 180s. Think I might have some 185s in the box but thos'd surely be too big.