I've been through several intake setups through the last couple years, and now I've got a new one and I just wanted to share for those who have similiar needs.
Long ago I started running lid free on the airbox for better air flow, and eventually I decied I didn't need the snorkels anymore because of this so I removed them, but this led to me being concerned about splashes getting into the holes that were left so I plugged them, as many have done. I've ran that way for 2 years. I went to carb mount for a while, but my gncc style riding places don't cater well to that so I went back to open airbox with snorkel holes plugged.

Well, newsflash, as Mr.Horsepower has proven and shared many times now, the intake boot with no airbox at all works much better than the clamp-on filter direct to carb - so much better that you will have to jet up if you go from carb mount to it. And in the carb shootout with the Lectron vs. Mikuni, THEBOM ended up with best power coming from a 170 main. So this got me thinking, is there more to gain by unplugging those old snorkel holes? I mean I won't go without the airbox alltogether because the creeks will have my intake for lunch. So I removed the plugs from the old snorkel holes today to make some full throttle runs and see what's up, and the bike was so lean it was totally dead from 3/4 to full. I jetted up one jet at a time, each time gaining more response on the top, until I ultimately settled on a 165 main. 170 gave me no more on top from the 165 except for a little soot, 165 is where I ended up going back to and staying.

Now I'm old school on tuning, no dyno here at my shop, its all about taking her up from a lean stumble until backing off a tiny bit from full throttle indicates an rpm change, and then knowing she's giving all she can, so take that for what its worth with a grain of salt, but I'm pretty sure I'm within one jet size of being spot on with a sniffer and it jives with THEBOM's setting of 170 during shootout day because right now its a little colder than it was that day, I run a disk system instead of open end, and I still got an airbox in place - its just breathing as much as it can now.

So anyway, thanks alot THEBOM and MRHP for all the testing, and sharing of tests, and to those of you with holes plugged, unplug 'em and jet up because I'm able to hit 300rpm's higher in 5th as a result so that's gotta coount for something.

 

Hightower, we have discussed many issue on this sight and I always seem to respect/agree the way you handle yourself and your opinions.
Mr. Horsepower has taken a great intrest to our Hobby and has stepped up to the plate. His Dyno work has proven to be very beneficial, and I hope that the dyno work continues. I would like to add that your help with our DS's has been equally as important and you continue to be a huge asset to our community. Thank you for all that you have done and I apprectiate the way in which you conduct yourself.

I agree that there seems to be a pretty good benifit going away from the Carb Mount filter. I don't really need the box but will definitely by going to the snorkle and K&N. I don't know if I'll go to the snorkle or make my own out of alluminum and polish it. I like the custom tube idea... I would think that a smooth run as apposed to the bumbs in the snorkle would be a good thing. Any time we can give air a chance to gain velocity and smooth it's path the better. I'll come up with something this weekend and let you guys know how it turns out. IF I can figure out how to post a pic, I will. Also, if it comes out nice, maybe I'll send one to MR. HP and have him dyno it as a third party participant. I'll do my own dyno work here and see if he can match the results.

Thanks again Hightower.

Also, can you give us some particulars on your sled and enviroment.

Carb set up and elevation would be great!

BigDaddy

 

This is what I was wondering also, BigDaddy, make that tube and test it out!

 

Hightower, it looks like you have done your homework to the full extent You have always had solid knoledge, I have researched also different theorys to form my own conclusions , The tm carbs do not like the velocity of the snorkle as we all know unless set with the exact jetting, I have been testing different set-ups for years and usually have ran what works the best on the hills. The only time I had good results with Tm45 +snorkle was with airbox in tack, without the lid, worked great on my stage 2.

I just installed a lectron 48mm HV with HOGGED out oversized intake along w/ snorkle on my 720... It seems to rev very quik but I still have to make a few minor adjustments( I have not taken it for a spin yet), It seems to be rich on the very top end when revving high RPMs, but overall I can see a huge flow difference compared to TM set ups... Also, It never made any sence to me to have the direct mount air filter smashed in between seat and frame.

I will give an update on the performance when I get to the hill or dyno, but first I need to get the lectron dialed in for my motor.

I had my TM dialed in great this last weekend, but I still lost a few bike lengths when the temp changed. That I cant afford.

 

thanks for the thanks guys, and once again thanks to those that have actually spent hard earned money with their testing. my testing is all in the seat of the pants environment and aint as definitive as the dyno, but its free and fun all at the same time, and done in the fields and country roads here at home.

that's real cool BigDaddy, I agree it'd be nice to elliminate the ridges formed inside the boot from the hose clamps.
my sled is a stage 2 stock bore, 11.5:1, A1/A2 cams, ported intake match ported to head, RWR cdi, TM45 165 main, needle on 3rd groove, 30 pilot, #50 pumper nozzle squirting right off idle to about 1/3 throttle on the travel limits, White Bros. Pro-Meg 18 disks. riding at 700' (basically sea level).

Thanks Annihilater, I'm wondering what my changes may be my next trip to Sand Mountain when it comes to hill shoots. And I'm also wondering how well the 48 lectron reacts to elevation changes going from sea level to say 5" in Utah and Idaho - keep us posted on your progress. oh, and ditto on the seat smashing....

 

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I NEED TO GO DUNES

 

racerx5x5:

Doesn't everybody?

Hightower: good post!

BigDaddy: go ahead and make that snorkel, everyone wants to see something to replace that lame rubber tube.

And a huge thanks to all of the guys who step up and do all of the new mods & such spending their money to see what works. The rest of us who only have enough cash to do it once really appreciate it. I could name names, but to be thorough I'd have to name about 20 - 40 guys From AZSand to whomever has a nickname that start with a Z.