Bonneville America Forums Forums Technical Forums Performance Mods To drill,or Not to drill

Greetings,I've got a "newbee" question.I ride a '07 America,w/ short TOR's, K&N,all snorkles removed,A.I. removed.The carbs were re-jetted when I bought the bike about 3 years ago when the new pipes were installed, but I don't know what jets were installed. Getting ready now for my big trip out west,2-up,and thinking about drilling my air-box!Long story short ,would it be worth it?

Don't do it just before a long trip. Do it when you have a enough time to fiddle with jets and possible have time to order them in.

Otherwise, HECK YEAH it's worth it. My second 2002 Bonneville America has a short TORs, and a drilled airbox with no snorkel, and it runs great. Unifilter in the stock location. The previous owner put screen/scotchbright over the holes to help protect it and sorta keep the water out. I rode it through BC in a torrential downpour and hail last July and it performed flawlessly. I haven't confirmed the jetting myself but the paperwork seems to indicate 135 mains.

Thanks FriarJohn,I've got about 6 months till the ride.Just wanted to get started early...my motto is it's always something! Sharpening my bits now!

Oh, then certainly, have at it.

I have a drilled airbox with a uni filter as well. I like it alot. I am running a bit lean though and will as soon as possible install larger jets including the pilots. I intend to go up to the 45 pilots, and 132 mains.

I have Specialty Spares for this bike with the drilled airbox. The only thing stopping me (um besides the cold, snow and unheated garage) from putting them on is rejetting. It's running so good right now I don't want to bork it up.

Chad, what jets and pipes are you running right now?

Home made open pipes 18" long 2" diameter 90 degree turn down no baffles. 130 mains thruxton needles 42 pilots no snorkles airbox drilled 5 - 5/8 holes looks like a dice. Theres a pic on here some where.

I took a few minutes this afternoon and was able to pull one of my float bowls...mains are 130's but don't know about the pilots. Stock needle and no shim.It's amazing what you can see with a inspection mirror and a magnifying glass!

Your,s and Dinqua's calculators say 133.5. But I,m not running that lean.

I've got a friend of a friend who runs the dyno at the local harley dealer...he said for 50 bucks he could run my bike.They wouldn't do any adjusting, just give a good starting point.Maybe I'll drill the box before we make a dyno pull?.And thanks for all support...BonnevilleAmerica Rocks!

Good luck and have fun.

im thinking when i did my airbox i had 132's with thruxton needles. felt like it ran the better than it does with the freak

I think the drilled airbox is probably the best option for an everyday rider. If you want a hotrod go pods and kill the airbox. But I can get good performance out of Reboot, and if I dog it and go easy I can get great gas mileage (and decent performance). I think it's the best of both worlds.

(of course, it doesn't sound like Bollox with the pods and Specialty Spares )

I'm really concidering going with pods, and ****** canning the air box.

I ditched my airbox the first year I had my bike, relocated the battery and installed pods. Pre-Freak and WAY before British-Customs. I also bought the short TORs right away. I don't recall any aftermarket pipes being available, maybe Sceptres from Team Triumph in Wisconsin but they were much more expensive. I don't really regret the path I took, but I should have just drilled the airbox, put a K&N in it and drilled the stock pipes. I would've save a lot of time and money and probably been just as happy. Now there are a lot more options.

Did ya get alot more power? I got home built pipes, no problem there I like 'em. I never much cared for after market pipes. I just want to get as much power as I can with out getting the 904.

With everything comes trade offs. The bike definitely woke up with the pods. Is there that big of a difference on the seat-of-the-pants dyno between drilled airbox and pods? Who knows? If I can get my pod-equipped bike running this Spring I'll compare and contrast. Good excuse to get my Veypor up and running...

you will likley need to go up on the mains, 133 or so might be a good place to start, not likley going to have to change the pilots, but it also depends allot on how many holes and how big they are, hmmm, not entirely sure how much more butt performance you are going to feel though?

I got a tremendous boost when I did what I have now. I wonder how much can be squeezed out of that 790.

Without cracking the case open or head bolts? Flowing exhaust, flatside carbs with pods and a custom CDI. And a nice long dyno tuning session. I think after that you're going inside the thing, although I suppose you could turbocharge it...

Whats a good cdi. I've heard too much bad about procom.

Doesn't TPUSA do custom mods to the stock CDI? I can't remember off the top of my head.

dump the box, do the freak, re-tune and new pipe and you will be good to go. Not sure why anyone would want anymore then that, bike bloody screams when you want, has more then enough torque and decet fuel mialage. Hmmm maybe thats just me? :-)

My pod bike gets lousy mileage even when I stay out of the throttle, but I think I need to work on the jetting. Ya know, if I can ever get it running again...

I'm going to.