Quote:
Originally Posted by rtking
You nailed it, 2LZ. I did a write-up in another link here:
http://chinariders.net/showthread.ph...highlight=dyno
I was using a conservative 10% drivetrain loss instead of 15%. But the fact is that the dyno is rear wheel, and the engine is delivering the advertised horsepower.
About performance... the muffler probably frees up a little (maybe 1 hp?) which is tough to feel. But the throttle response is good with the aftermarket muffler.
With the K&N filter (and this is based on riding around the parking lot near my house), the bike feels like it's breathing better and is more responsive. I don't know how much of that is wishful thinking vs. actual performance. My "test" will be next weekend when I can get in a ride and see if there's any top speed and drivability improvements.
In terms of the part - I want to re-measure the throttle body as this filter (K&N part number RC-1290, 48mm inside diamter) is a little big for the throttle body. I think the cone filter the Grom riders are using (K&N part number R-1100) might work better with its 43mm inside diameter. And whatever filter is being used, having a 10 degree (or so) bend is necessary to clear the airbox (which I sealed off with foil tape for this experiment.)
Bear in mind that in this location, the filter will be exposed to a lot of dirt and moisture. I plan to purchase a Filterwear Pre-Filter for the cone filter to help filter dirt/dust and water. I'm also planning to use some aluminum tubing to extend the filter into the stock airbox (and make some more breathing holes) to see if that makes a difference.
Like I wrote... I love to tinker.  |
Thanks for the excellent info rtking!....and it seems we are co-tinkerers... ;-)
In all honesty, it's the throttle response, under load, that I'm more interested in clearing up, not just HP gain. Seems anything under 5k at all...and it's "Bawwwwggghhhh" until it really winds up. The 13 tooth helped but it just sounds so choked up sometimes. Almost like an old Honda 90 on steroids.