Aftermarket Intake Piping Replacement (NK Racing)

[stopper]

Hey All - In my quest to get a tiiiiny bit more oomph out of the little Trail (the mrs and I are about 330lbs plus gear) without major modding like big bore kits or ecm tinkering, I figured restrictions in the intake and exhaust were easy enough to alleviate and still be reversible if needed.

I've already put on a new exhaust (I picked up the last black heat-resistant coating Moriwaki Monster exhaust in stock on Webike about a week ago and I absolutely LOVE it), but now I'm looking at the intake channel. I saw a few ppl on here talking about the biggest restriction being the piping between the filter and throttle body, not the snorkel or filter itself. In other words, this:

Then I came across this:

It seems to be made by NK Racing out of Thailand, and their Facebook page shows that they do a ton of modding/racing on scooters and small cc bikes, and the like. They show a "before and after" dyno graph too but to be honest, those always seem dubious at best, and mostly marketing.
The only place I can find it for sale is their own Thai-based shopping page: HERE, or from various sellers on eBay.

Anyone out there try this yet or heard or anyone trying it? Do you think it's worth a shot to help the lil Trail breath easier? It requires cutting a wider hole in the stock plastic intake box but I checked on Partzilla and that plastic piece is literally only $8, so you could easily just buy a new one if you wanted to go back to stock.

 

[m in sc]

if it were me, id go with a section of silicone hose. that things ridiculous.

 

[stopper]

if it were me, id go with a section of silicone hose. that things ridiculous.

HAHA! To be fair, it is slightly absurd-looking for our 9HP beasts. It does disappear a little bit in the photos where all of the plastic covers are back on, but that extra side "resonator" tumor is a bit...much.

 

[dmonkey]

I would not expect that resonator chamber / boost bottle / "mini bomb" to help with performance.
Long and colorful explanation here (NSFW language)

 

[m in sc]

agreed. i mean its a 26?mm throttle body. i think slightly bigger is better. i saw that thing on the ebay for like 86 bucks shipped. IF i were to get one id cut the tumor off and tig it back up smooth.

 

[stopper]

Another thing I was also thinking about...I've always been morally opposed to fake vents, grills, and "performance-looking" stick-ons on cars. I've been staring at this thing on my Trail for a couple months now...



and I can't help but think that it's supposed to look like an intake grill. I'm about two beers away from convincing myself to dremel that part out and replace it with a real black metal screen and have a nice, bigger, fully functioning intake opening. I could see that exposing the filter to a lot more debris though, but I do 95% of my riding on pavement. There's no way I'd be considering this if I was playing in dirt, mud, and dust all the time.

 

[dmonkey]

They might have done that to break up the colors so that side of the bike isn't overwhelmed with the body color like the Trail 110 was. When you pull the red plastic body panel off you'll see that the left side of that black filter box cover just has a different style of screen texture to it, so likely some functional purpose to it such as rigidity.

There's also this as an interesting aftermarket solution: https://japan.webike.net/products/24652206.html

 

[m in sc]

it continues the shape of the decal on the side-cover.

 

[m in sc]

regarding the boost bottle, Yamaha started doing this on production ( 2 stroke) vehicles in the late 70s early 80s, I think 1st use was on a liquid cooled dt50. the banshees run them pretty regular, and I run them on 2 of my rds. and yes, they help at a specific range ... right at 5200~5400 rpm on the rds (volume is 240 cc) to combat the reed reversion. On the banshees its at a lower rpm and the bottles are notably bigger. it gets VERY complicated math wise... and i sure as hell cant see any actual development going into this particular part to make it worth while. except as said, as a 'marketing' thing

 

[rundmm]

Been looking all over for a air intake that is like the grom or the monkey, is that not something that can be done to the trail? Same engine and everything right? Is there a reason the chimera would/does not work?

 

[stopper]

There’s this one on Webike…very similar to the Chimera ones you might be referring to (which is essentially a short pipe open air cone filter): HERE

However, in translating the Japanese on those dyno graphs on that page, which I imagine are to advertise FOR the product, ironically, it’s worth noting that on the stock CT125 (stock exhaust, stock camshaft and tuning, no big bore kit), that the intake actual appears to HURT performance all the way up to 6100rpm. A gain of <1hp gain shows up beyond that to redline. So unless you’re always winding out the lil 125cc, or more relevantly adding this into the mix with a bigger head, it’s a waste of time even by the mfg’s own admission.

 

[rundmm]

Thank you for that info. Not always winding it out but on my commute to work, I try to stay at 50 because it is highway for about 4 miles and against the wind, it is almost impossible. Cars come up fast, even on short stretches of road.