Airbox modding

[mik_str]

Markus, as you are talking 3 hp in the mids, may I assume 2-4 lb-ft of torque then? did the peak torque number go up?

cheers

[Tweety]

Markus, as you are talking 3 hp in the mids, may I assume 2-4 lb-ft of torque then? did the peak torque number go up?

cheers

Peak did go up slightly, but more than that it spread the peak out, and brought the ends of that curve up a little... Removed a few little lumps that had been annoying me... ;)

I'm not quite happy yet... I'll squeeze even more out of this engine sooner or later, but we're getting there...

Oh, BTW the race engine is in the chassie, should dyno in a couple of days... That should beat this one hands down...

[mik_str]

thanks bud

Keep us posted on your race bike (dyno numbers, and pics too, would be nice).

cheers

[mik_str]

I have been playing with the fuel screws for a bit, since installing the modded filter, making it leaner in small incremental steps and have now got it spot on. Throttle response is amazing everywhere, it pulls like a freight train, and I just got back from ride (riding my normal street pace, average speed 100-120 km/h with a lot of roll-ons and a few quick runs through gears) and got 200 km before the RLOD came on

Mission accomplished, am very, very satisfied with results

[lloydie]

I only need a few more little bits before my mk3 begins :-)

[tony.mon]

My mk 3 parts have mostly arrived, and here's what I plan to do.
Firstly, I want to increase the airbox volume as much as is possible. This means making a new airbox by using a dummy frame, engine, carbs set I have, and laying carbon fibre matting into the void, keeping the movable carb links and front cct out of the way, but going right up to the front heat shield area.
I plan to introduce fabricated ram air tubes in through the triangular gaps in the frame, the RH one has the throttle cables running through it and so I'll need to modify those a re-route using longer cables, or change the routing one way or another to leave those triangular holes clear.
The LH one is clear, as I have stick coils fitted.
Once I have a carbon tub I can arrange to seal it against the underside of the tank.
So far so easy.....
I have one side of a fairing so far, and need a LH side to cut up. If you look at a pic of the bike side-on, you'll see where the fairing has a sort of bulge, the line directly from the section underneath the headlight section doesn't follow a straight line down to where the winglet pokes out. If you cut along that imaginary straight line, you end up with a hole, just forward of the rads. I have to move the rads back a few mm to clear the usd forks anyway....
That's fine for cooling the rads, with a bit of mesh in, and frees up the triangular air intakes near the headlight for ram air.
Sealing those ducts up won't take a lot of doing, and then routing it to feed smoothly in through those triangular holes in the frame is the last thing to do there.
Once we have cold high pressure air flowing into the airbox, it needs to be filtered. I plan to use the triangular section behind the headstock, usually above the heat shield, and that's going to be the new pre-filter section. Fitting a rectangular filter vertically across the rear of what was the triangular heatshield area should now be possible.

OK, I now have ram air, and a filter, with a larger volume of airbox. I removed the catch bottle and pipework from the airbox ages ago.

I'll be fitting variable stacks, and so with ram air I'll need to keep rejetting- it'll be a lot of faffing around, and generally dynos aren't good a t duplicating ram air effects.
So I've bought a main air jet version of the Flo Commander, which gives me a chance to adjust main jet size on the fly, and if mounted up externally to the air box, next to the clocks, I can adjust it on the go.
This should enable me to tune to stack up, lots of ram air situations just as easily as stacks down stationary on the dyno tuning.

Stacks, by the way, will be controlled by a thumb rear brake setup on the LH bar, initially, anyway, I might yet get them motorised and automatic, once I've decided when they should operate.

That might be enough to be getting on with for now, although I might add the pilot circuit Flo Commander if it looks like the gains are worth the cost.

So far I have some of the parts, and need to get on with ordering the carbon weave sheets and resin. It probably won't be pretty, but I hope it will be functional.

The last part of the jigsaw, once all of that's sorted and running cleanly, will be a custom exhaust, with a sump modification, the downpipes having individual Lambda wide-range sensors fitted which, with two gauges on the dash area, will help to let me tune the flo commander to each rev range/ load/stack position setting.

Apart from that, the engine mods, and I've now got most of the 929 front end bought, just wheel, mudguard and 2" rise clip-ons to go.

That should do for this winter's activities, may take me through to the spring as well.....

LLoydie, is that pretty much what you were planning?

[lloydie]

Looks like you will have your hands full :-) .

I'm planning ram air for sure with a large tub airbox but I'm still thinking about how I want to go about it (hidden or exposed tubes)
I want to go a long these lines with it
as there's less crap in the air box to cause turbulence . I'm thinking about having the air feeds going in on the floor of the air box and having a few baffles to smooth out the air flow .

I am also planning on making the road bike air box even bigger once I've learnt how to sink the plastic without scrapping it .
I've already made a start on a larger gutted air box to be used with no lid and different velocity stacks but with the air box being smoother internally to help reduce turbulence . I'd like to have one finished by spring for testing in the Dyno .



Good luck tony

[darkember]

I believe Adyf's plastic bag mode works a treat

[lloydie]

Mk3 finished

This one has been made for moriwaki stacks and has been slimmed down so the stacks sit flush in the carbs.
The moriwaki stacks are made for the ram air box so the fit directly to the cars and this is why on the mk3 I had to remove a lot of material from the air box so the stacks fit .
Tho this has been fitted just for a few tests on kermit but was made for miss piggy and will run no lid and a piper x filter or k&n .

[tony.mon]

Not sure you'll enjoy the no airbox lid, but give it a go.
I found no power at all below 7000, then everything.

All I missed was the two-stroke haze and smell!

I made one out of cardboard, then covered it in gaffer tape:


Then covered that in PVA glue.

[lloydie]

It will be fitted to the tuned engine when it's built and then set up with no lid .

I'm liking to template tony
Remember you will need some holes in it for fuel pipes and try not to have any corners just smooth flowing bends

[seb421]

looking at other bikes in comparison the GSXR 1000 and the Blade have what i would consider to be bloody tiny airboxes compared to the storms standard one

except the both are fed via ram air method and Fi

Get Ram air fitted to the storm box would be my first point of call to try for gains

be interesting to see what yeti's bike would make on a back to back dyno with the Ram air fitted and then taken off providing it was a decent dyno with good blower on it

[mik_str]

looking at other bikes in comparison the GSXR 1000 and the Blade have what i would consider to be bloody tiny airboxes compared to the storms standard one

except the both are fed via ram air method and Fi

Get Ram air fitted to the storm box would be my first point of call to try for gains

be interesting to see what yeti's bike would make on a back to back dyno with the Ram air fitted and then taken off providing it was a decent dyno with good blower on it

don't forget too that an I-4 takes four, regular timed gulps of air (ie. 250cc on a literbike), whereas a V-twin takes two, rather large (ie 500cc) and asymmetrical gulps, hence the need for a larger volume on a twin.......

[tony.mon]

don't forget too that an I-4 takes four, regular timed gulps of air (ie. 250cc on a literbike), whereas a V-twin takes two, rather large (ie 500cc) and asymmetrical gulps, hence the need for a larger volume on a twin.......

Exactly so, and that's why it won't run right over 5K with the timing 180 degrees out. The airbox simply can't refill in time after the first cylinder has gulped in all the air before the second one tries to get some, too.

With the timing set 180 out there's only 90 degrees- of crank rotation between gulps- not enough.

Now with a larger, divided airbox, so that each cylinder has its own airbox, fed with ram air, well, that would be different.......

[lloydie]

Tony do you think more power could be had from running it 180 out with a twin air box or no air box

Might be something to try when I get board one day :-)