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08-23-2007, 5:07 PM Babaganoush Joined on 03-23-2007 SouthCentral Pennsylvania Posts 960 AIR BOX MOD- UPDATED 11/24/07 Attachment: IMG_0336.JPG OK, here is something to chew on. I modded my air box recently by drilling a series of holes as shown with a 5/8" Forstner Bit. This is a specialized wood cutting bit that makes very clean cuts. I chose to modify the cover only as it can easily be restored by buying a new one for about 30 bucks. The holes are above the outside cover line so none of the holes are directly exposed to splashing from stream crossing, etc.. They can easily be covered up with duct tape (quack-quack) if you need it. You can see I have the option of drilling many more if I need/want to. I don't believe in pulling the snorkel because it just shortens the air path to the carb- it doesn't open up more area by itself. I have to get the bike State Inspected every year and can't make massive changes anyway without risking a flunk and a redo. Hope this helps in your modding decisions. Dave "LOUD VALVES SAVE LIVES" -back side of Royal Enfield T-shirt    Report

08-23-2007, 5:08 PM Babaganoush Joined on 03-23-2007 SouthCentral Pennsylvania Posts 960 Re: AIR BOX MOD Attachment: IMG_0332.JPG Here is the outside view. "LOUD VALVES SAVE LIVES" -back side of Royal Enfield T-shirt    Report

08-23-2007, 7:11 PM steves10 Joined on 02-04-2007 San Diego, California Posts 685 Re: AIR BOX MOD Dave, The $64,000 question: did you need to rejet after this mod? Steve (nice job on the holes, BTW)    Report

08-23-2007, 7:42 PM Babaganoush Joined on 03-23-2007 SouthCentral Pennsylvania Posts 960 Re: AIR BOX MOD Hi Steve, Actually, I rejetted first and raised the needle. I drilled the air box because it seemed to be running rich and squirrelly like the choke was on. Turns out I only needed to turn in the idle screw from 3 turns out to 2 3/4 turns. Runs well (super pull 6-9000rpms) but I think I can do better. If not, I can always put it back to the last good mod. Don't tell anyone but I am experimenting using a Colortune plug. Not sure how useful it is yet- that's why I haven't posted on it. Dave "LOUD VALVES SAVE LIVES" -back side of Royal Enfield T-shirt    Report

08-28-2007, 9:08 AM bturmel Joined on 08-16-2007 Gatineau Posts 4 Re: AIR BOX MOD Did it improved the performance ? BenBen 2004 - Yamaha TW200 / Gray & White 2006 - Yamaha Kodiak 450 / Blue 'Life is beautiful'    Report

08-28-2007, 1:49 PM Babaganoush Joined on 03-23-2007 SouthCentral Pennsylvania Posts 960 Re: AIR BOX MOD Hi BenBen, Improve performance? Hard to say right now as I am still futzing around with the needle jet spacing on a 127.5 Mikuni jet (not same-same as Teikei jet sizing) and the idle mixture screw. I have the needle jet spaced an extra .04". Seems like you can get a heck of a boost in power (mid-range) with just a larger jet, needle spacing, and opening the idle screw to enrich the mixture. I suspect the air box mod is only going to help at wide open throttle or close to it. I am keeping the muffler stock. I was out the other day testing the latest incarnation and it was running pretty sweet up to 60 or so (remember, 52 tooth rear sprocket). I was not riding anyplace where I could open it up and check the top speed. Once you get up into the 9-10 grand RPMs the engine will either seem strong or start whimping out on you. This is where your air box/ muffler mods really would make a difference- me thinks. I would not ever open up the air box without enriching the mixture since a stock TW is running SO lean you will be running really hot and toasty and might end up in Seizure World. (The name of a retirement community in Maryland A.K.A. Leisure World. Sick humor, sorry.)  I have noticed the engine running much cooler since I have put in the larger jet and opened up the idle screw. Down at least 20 degrees or more. Dave "LOUD VALVES SAVE LIVES" -back side of Royal Enfield T-shirt    Report

08-28-2007, 6:11 PM steves10 Joined on 02-04-2007 San Diego, California Posts 685 Re: AIR BOX MOD Great report, Dave.  It's good to see someone going at this methodically. Steve    Report

08-28-2007, 7:32 PM Rman of 237 Joined on 05-04-2007 Northern Fayette Co. TX. Posts 1,055 Re: AIR BOX MOD Baba, keep tinkering with it! Your getting somewhere. It's not in vain and it's fun!! I believe that my TW has finally found it's place in the sun at last via "free mods", an unrestrictive exhaust and the ability to see through the concrete barriers that seem to manifest themselves in life (and on this forum) of institutionalized theory. The only way I can ever neglect this engine now is to return it to it's stock form which I assure you I will not do. R....... PS.. Epoxy a piece of wire screen to the inside of the holes.   '06 TW200 '06 XR650L uncorked '98 XR440R trick and plated '94 KDX200 '84 RZ350 '83 XR350R '84 ATC125    Report

11-24-2007, 6:20 PM Babaganoush Joined on 03-23-2007 SouthCentral Pennsylvania Posts 960 RAM AIR MOD Attachment: IMG_0383.JPG This is an extention of the Air Box Mod I originally posted- the next and possibly final stage?? Can't say what might be next. This is not a true ram air setup to me. I would think a tube from the carb opening to a funnel pointing to the front of the bike in the airstream would be the real deal. I did the next best thing by modifying the air box cover and outer side cover. I have spare parts to put the whole thing back to stock in a jiffy (side cover and cleaner case cap). Anyway, the pics show the number of 5/8" holes drilled in the cap (forstner bit) along with 9/16 foam weatherstripping to trap the air flowing in between the cap and the side cover. The side cover has the leading edge Dremeled off and sanded with a small Dremel sandpaper drum. The metal scoop is a furniture cup handle from TrueValue Hardware ($5). The scoop was mounted first and then the opening was marked and cut out with a small router-type bit (go slow- the bit will rapidly get clogged with melted plastic and harden) and a cut off wheel (Dremel). I used a short piece of washer hose slit almost in half to fill in the gap in the drop off of the side cover (this maybe could be caulked). The last part is the longer (about 1") 5mm metric screws with a couple of washers and 1/2" spacers. This keeps the side cover from closing too much of the space between the side cover and the cap. That's all for the technicals. How does it work? Short answer- IT RIPS! I finished it up last night and knew I would have to try it out today no matter what. The morning was bright sunshine but the temps were 25 F at night and in the low 30's when I went out. I bundled up as much as I could and took off to terrorize the countryside for a short test ride. Totally amazing! Wow, talk about breathing easier, uncorking and all that. I looked a lot like my Avatar this morning with a big grin on my face. It is never going to be a crotch rocket but it is pretty darned good and fun. I came back to the house after a 20 mile run with cold fingers and knees but it was worth it. I can see where I need to start raising the needle a bit on the carb to richen it up a bit again. So the total package is NGK Iridium plug, Ram Air Mod, Ikat Spark Enhancer http://tw200forum.com/forums/23077/ShowPost.aspx , and Carb Mod  http://tw200forum.com/forums/18477/ShowPost.aspx . I say go for it if you've a mind to.   BTW It was too darned cold to be fooling with a camera today so you'll just have to "Trust me" again.    Dave "LOUD VALVES SAVE LIVES" -back side of Royal Enfield T-shirt    Report

11-24-2007, 6:21 PM Babaganoush Joined on 03-23-2007 SouthCentral Pennsylvania Posts 960 Re: RAM AIR MOD Attachment: IMG_0386.JPG Cap cover mods. "LOUD VALVES SAVE LIVES" -back side of Royal Enfield T-shirt    Report

11-24-2007, 6:22 PM Babaganoush Joined on 03-23-2007 SouthCentral Pennsylvania Posts 960 Re: RAM AIR MOD Attachment: IMG_0388.JPG Side cover detail "LOUD VALVES SAVE LIVES" -back side of Royal Enfield T-shirt    Report

11-24-2007, 8:51 PM JoMomSophat Joined on 07-12-2006 Seattle WA Posts 803 Re: RAM AIR MOD The foam you have there is a really good idea. It would limit the turbulant air running across the holes and it might help to direct the air into the box. as far as "ram air" even the best ram air (suzuki gsxr) doean't star to make a difference until at least 80mph but it looks cool with all the stickers that you can point out to people admiring your bike. you should put a "ram air" sticker on your side cover so there will be no question what that thing with the holes and the cones is doing in your plastic GO_SEAHAWKS!!!    Report

11-24-2007, 10:03 PM riccio Joined on 08-17-2007 macon county Posts 160 Re: RAM AIR MOD i dont intend to "piss on your parade" but keep in mind with your amazing results, it was 30 degress outside, thats some serious COLD AIR INTAKE no mater what kind of mod! all in all it does look sweet! and im sure it does give a nice boost well done!    Report

05-27-2008, 12:02 AM Jimbo C. Joined on 10-15-2007 Bonita CA Posts 528 Re: AIR BOX MOD- UPDATED 11/24/07 That is about the coolest DIY RAM mod I have ever seen.( The Only one I seen for the TW)I wish we had a DYNO run prior to any of the preformance mods. this "Seat Of Pants" dyno is ok though, Cheap, if nothing else. I like the spherical drawer handle idea, I wonder if your leg position would affect the pressure/flow. Very Very Cool Dave! Thanks for stirring up the neurons. Regards Jim. For Ordering instructions or inquiries, email me @ trailwaycafe@cox.net Provide: Full Name and Forum name(if possible.) Shipping Address. Phone # And Color Preference(Grey,Amber, Dark or Light Blue)if ordering. RIDE WELL EVERYONE!    Report

05-27-2008, 6:14 AM Babaganoush Joined on 03-23-2007 SouthCentral Pennsylvania Posts 960 Re: AIR BOX MOD- UPDATED 11/24/07 Hi Jimbo, I can let you know that this mod really works. I recently put the stock cover back on (I have stock parts for passing state inspection- not sure if they would fail it because of my mod) and it took forever to rev up through the gears compared to the mod. I think if your leg is too close to the tank it can block the straight-in flow. I would have preferred to have the end of the intake forward more but did not come across anything I could use. My only concern is not to run too lean at top speeds. I was experimenting with a 132.5 Mikuni main jet and a little more needle spacer height which seemed to be working pretty well. I don't think a dyno would give a true test since the mod depends on the bike moving to shove more air into the intake. The good thing about this mod is that it can be completely undone by simply replacing the two covers. Despite the naysayers and the wet blankets out there, it is a keeper for me. The bike really rips through the gears with the IKAT (or Direct-Hits), larger jets and needle adjustment, and the Ram Air Mod. I still have a stock exhaust. I guess I am more of a hot-rodder at heart (see avatar). Somebody running in lots of dust off-road or just trails would not need or want this mod. Dave "LOUD VALVES SAVE LIVES" -back side of Royal Enfield T-shirt    Report

05-27-2008, 1:55 PM Jimbo C. Joined on 10-15-2007 Bonita CA Posts 528 Re: AIR BOX MOD- UPDATED 11/24/07 Mabie!?* I would just ride it that way untill I got out to the dez (50-60 miles)and then pop the cover off whip out my little roll of duct tape. Might take 2-3 minutes and your back in the SNORK mode for the sandy washes. It would probably run a little rich on the slow trails and that isn't such a bad thing! Baba, I was out running on the freeway hauling some grey plastic from the Plastic store and I reached down with my hand, where the little scoop you made would be and discovered that there is alot of air pressure down there comming out from behind my leg!!!, I think it is possibly an excellent spot, I would bet that if you hung a barometer & pitot tube in that area you would discover that you couldent have picked a better spot without making it (a RAM)look like a French Horn. We need a wind tunnell with a dyno inside it Bro!!! :) For Ordering instructions or inquiries, email me @ trailwaycafe@cox.net Provide: Full Name and Forum name(if possible.) Shipping Address. Phone # And Color Preference(Grey,Amber, Dark or Light Blue)if ordering. RIDE WELL EVERYONE!    Report

05-27-2008, 2:20 PM JoMomSophat Joined on 07-12-2006 Seattle WA Posts 803 how much ? I understand that the mods make the bike sound (feel) different but how much hp do you think you are getting with the air box mod 10hp? 20hp? or maybe a % figure. is it %50 faster ? GO_SEAHAWKS!!!    Report

05-27-2008, 3:35 PM Babaganoush Joined on 03-23-2007 SouthCentral Pennsylvania Posts 960 Re: AIR BOX MOD- UPDATED 11/24/07 Hi Jimbo, You are right about the duct tape. I suggested that on another post when someone cautioned about air box mods and crossing rivers, mud holes, etc. Glad you felt more air pressure at that spot. I was only looking for a straight-in funnel. I wanted to cut away the leading edge of the side cover (and did) but felt the frame was blocking the airflow I wanted to get in there. That is why I added the cup handle cutout. I would like to have tried a bigger scoop but could not find anything right off. A while back some guy who had access to a motorcycle shop did a lot of mods and said he also made a ram air intake from 1/2 PVC cap. He never did show it or any details. I think he was also the  guy who installed a custom disk brake on his rear tire. Another point. Just drilling holes in the side cover did not seem to buy me any more performance until I added the scoop and the foam stripping to trap and force the air into the box. I thought about adding more scoops but I am not sure that will help much unless they get larger after the first one. I would really like one that is about 2" X 2" and 6" long. That would seem to allow the max amount of air to be shoved into the air filter box. (Your next plastic project, Jimbo. ---Just kidding.)  Dave "LOUD VALVES SAVE LIVES" -back side of Royal Enfield T-shirt    Report

05-27-2008, 4:08 PM Babaganoush Joined on 03-23-2007 SouthCentral Pennsylvania Posts 960 Re: AIR BOX MOD-UPDATED 11/24/07 Hi JoMom, It is really hard to put a hp increase on the mods. The sense I get is that I am just getting the most out of what is there. There is really no difference in the sound or feel of the bike except that when I started using larger jets, I noticed the exhaust note got quieter and less annoying  along with a drop in operating temperature at speed. I judge the success of a mod by how fast it can pull me up through the gears and still act normally at all revs, loads and at idle, starting, choke, etc.. I have my Vapor tach  yellow light  set at 9,800rpm and red light set at 10,000rpm. Adding larger jets and needle adjustment gave me more noticable pull and put a smile on my face. Adding the IKAT layered more performance and pull on top of that. The Ram Air Mod added onto that. My 'testing' is simply maxing out in 2nd, 3rd and 4th. If the bike can pull me quickly and easily to make the lights light up and not seize or act up, that is a good mod. The other 'test' is whether I break out in a big smile and declare "Holy Crap!" to myself. Sorry, not very scientific-- just having some fun. Dave BTW I have seen your other post on another thread poo-pooing the Ram Air Mod. First of all, I am not selling anything. Second, I don't care if anyone thinks it works or not. I am just sharing what I have done that improves the performance of my bike- believe it or don't, I don't care. If I had to get approval from the 'authorities' on any subject, I wouldn't have done 3/4 of the things I have done so far- and I am not done yet. Now it's time for some Pork and Beans-  http://www.youtube.com/watch?v=muP9eH2p2PI "LOUD VALVES SAVE LIVES" -back side of Royal Enfield T-shirt    Report

05-27-2008, 4:44 PM Jimbo C. Joined on 10-15-2007 Bonita CA Posts 528 Re: AIR BOX MOD- UPDATED 11/24/07 I am listening Baba! I am already teaming up with a friend at work to learn by doing, carbon fibre layup techniques. He wants to know how to make trick stuff for his KTM and I want to make repeatable trick stuff for my friends here. I see this as an easy project. The tougher one is the C-fibre rear fender, and rotomolded rear sub frame fuel tank. I dont want to slow progress on adapting a larger fuel tank for the TW but I like the way the current one looks, I have to figure out a slick looking way to do it safely. I have an extra Air box to play with and a set of extra side covers, so I just need to practice making a few RAM side covers for the air box and then make a mold for the same. JoMom! I'm with you on the scientific method thing, I tried to get a objective test criteria set up for my shield but you know what , Most of us here are just enjoying ourselves playing around. sometimes creative people loose their creativity when the micrometer comes out. Inexpensive pocket dyno I do not have, But I am considering getting these mods together prior to install and paying $116.00 for a dyno Run before and after. Lee's Cycle has a good shop for that here in inSane Diego. (you can put a secondary blower on the RAM, but you have to calibrate the intake pressure to external conditions. It's been done before, Ive seen it back in 1977, Nothin new) For Ordering instructions or inquiries, email me @ trailwaycafe@cox.net Provide: Full Name and Forum name(if possible.) Shipping Address. Phone # And Color Preference(Grey,Amber, Dark or Light Blue)if ordering. RIDE WELL EVERYONE!    Report

05-31-2008, 8:20 PM FIRE UP Joined on 10-07-2007 RAMONA, CA Posts 187 Re: AIR BOX MOD Babaganoush,        Can I ask what year is your bike? I have two. An '03 and a '94. We just bought the '94 and although it seems to run really well, it has some slight hesitation on cracked throttle when on the colder side. I can start it on full choke and run the pants off of it right off the bat, (I normally don't do that) but if I take the choke off too soon it hesitates with slight throttle. Once you give it more throttle, it does really good. They are both California models if that tells you anything. My '03 doesn't seem to have the same glitch. I've taken the carb apart on the '94 to see if there's any gunk in the float bowl but, it's clean.      So, my question to you is: since you say most TWs run lean, what mod do I do with stock air box and exhaust still in place, that might help with the slight hesitation? Thanks  Scott Scott & Karla '03 TW 200(C) '94 TW 200(C) 18 mon 'till RETIRED!    Report

06-01-2008, 10:18 AM Babaganoush Joined on 03-23-2007 SouthCentral Pennsylvania Posts 960 Re: AIR BOX MOD Hi Scott, First, you should try opening up the idle screw underneath the carb. Find out how many turns it is already out by turning it CW until it seats. Count the turns as you are screwing it in. Once you know where it was you can open it CCW 1/2 to 2 turns past where it was. This should richen up the idle and off idle area that you are having problems with. BTW my bike is an '07 with the TK CV carb. Once you solve that problem and want more power you can start installing bigger jets and needle spacers as in: http://tw200forum.com/forums/18477/ShowPost.aspx and  http://tw200forum.com/forums/28873/ShowPost.aspx  .  Stock turns on the idle screw for me was about 1 1/2 to 1 3/4 out. The problem you describe in Centerline's thread is the kind of problem I was having when my mixture was too rich- an unevenness and bobbling, jumping back and forth of the drive chain. That was happening in 4th gear at speed. Check your rubber for cracks or leaks between the carb and engine intake. Normally I would suggest worn carb parts (housing at the butterfly stem) but your carb only has 350 miles on it. I would not suggest any Mods until you get this stock problem fixed. It is hard enough trying to dial in a larger jet and needle spacing without some other problem going on at the same time. I am also not sure if you don't have some gummed up passages in those little pin hole openings in the carb. I would spray carb cleaner and compressed air anywhere you find a passageway. I would soak the carb overnight in parts cleaner (Gunk makes a gallon can with a parts tray in it.) if you can remove all the non-metal parts from it. When I say compressed air I am not talking about one of those aerosol cans. I mean air coming from a compressor with preferably a rubber nozzle with a small opening (everyone has one, right? Just kidding. That's OK, I don't have any welding equipment either.). That is about all I can think of at the moment. Hope this helps. Dave "LOUD VALVES SAVE LIVES" -back side of Royal Enfield T-shirt    Report

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