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I installed my BC billet manifolds today:

BC Billet Intake Manifolds


This is a two-piece arrangement; the intake to head segment is billet, & carb to intake segment is hard rubber.

No pics yet, no test yet.

Initial impressions:

Pro:
- I like billet
- Stronger than OEM
- No need for a carb brace (although I used my patented heavy-duty ghetto-engineered zip tie)
- Potentially improved flow

Con
- $$$$
- Cheap-looking vacuum caps (a/k/a squirrel condoms) supplied
- Different size fasteners used; intake to head uses 4mm hex wrench, carb to intake uses 5mm hex wrench
- Minor "gunsmithing" fitting required with a precision file to get the carb to intake section mounting bolts to mount up properly
- Poor design for intake to head lower mounting bolts - can't get a straight shot at the bolt head. Fortunately I had a ball-end allen wrench that enabled me to tighten those fastners, otherwise TS, no joy. BC doesn't mention that. All they would have to do to fix is is machine relief/clearance notches in the underside of the billet intake. But noooo...they didn't. Looks like I'll be looking for a custom hex wrench as a work-around.

While the manifolds were off I did some light intake port cleanup work with hand-files, just to remove some rough edges inside of the machined mating surface at the head.

Pics of the newly mounted manifolds to follow when I get around to it.

Bonus installation tip: a light smear of grease in the o-ring channel will retain the o-ring in place while installing the manifold.

Here are some pics of the installation...

Port side:



Starboard side


This shows the whole setup on the starboard side, including the Uni mounted to the velocity stack:



So far I started the bike & it fired right up. The bummer is my AF gauge isn't getting juice, so something must not have been properly reconnected. I need to pull the tank and check.

those are tough to get on and to get tight, i had to cut a ball end hex short so i could get one on tight,the frame side bottoms are frigin horrible and i am sure they are not on as tight as they could be but seem ok regardless. i also powder coated the intakes so they do not end up going purple, many of them do. Poor design for sure.

Great idea on the powder coating. At some point I may notch the lower mount and have the billet portion powder coated.

Thx for the write up. I'm definetly not in the market for a set anymore!

Got some of these from newspeedmaster.com a number of years ago and had no problem with them at all. Unfortunately I don't think they are offered any longer.

hate to break it to you, but parts aren't engineered for the convenience of the mechanic, ever. the running joke is that mechs steal the engineers' girls.

The ones I got from Carlos may be just a tad longer because my filters on my bike appear to be back farther against the frame.

Finally got the bike out to test the new manifolds...main jets & needles seem OK, pilot screws can go a little richer.

The bike was also running leaner WOT with the new manifolds, so I went to 150 K mains from 148 K mains.

i was running on the rich side anyways , funny though i did notice a difference in the mountains that i had not noticed in the past so maybe i did lean it out more than i thought.

Thanks for the write up! I was considering getting these, mostly because the stock manifolds look kind of unfinished compared to the rest of the motor.

Sounds like it's not worth the effort if I'm not pushing for performance gains as well.

well they can be a pain but i still like them, they are solid, they look nice and you get a bit better flow to boot, i would do it again, just wish they were an easier install is all.

Currently running the OEM manifolds. I'm going to get around to notching the BC manifolds for better hex wrench clearance & paint the annodized portion hi-temp satin black. I will also port-match the heads to the manifolds at the same time. I will get to this sometime in the next few months. Then reinstall and back to the dyno. I expect this to be the only change for the next dyno run (see CV carb tuning thread for last dyno).

I port matched my stock intakes awhile back, but when I put them on the final time after the filing and sanding, an idea came to mind to drill and taper ream two spots in each intake so I could pull them off and replace them exactly where they go without a fuss. There is very little material on the flanges and even with the smallest taper pins I can buy, feasibility looked iffy. As I do not have a set of aftermarket ones as you do Ken, is there more meat on the head side flanges of the intakes you have over the stock examples? Just in case your not quite following what I'm talking about, precision bolted together machine assemblies are often completely built as a whole unit on the factory floor. After all is together and the units are aligned for the final torque up, where the units/components go together, undersize holes are drilled through both, then using a tapered reamer of a specific number size is run through the pilot hole and a matching tapered dowel pin is pounded into place. Now the machine is disassembled, shipped to the buyer and as it is buyer re assembled, the dowel pins are re installed and the factory determined alignments are easily re achieved...K? Come to think of it, roll pins might work almost as good, and they come smaller. But I would still like a little more metal, so I can stay clear of the o ring grooves.

The OEM manifolds & spacers are lightly port-matched to the head on my bike, just enough to smooth things out.

The BC manifolds have swirl cut-outs that will involve removing a bit more metal from the heads in order to properly blend the airflow. A little dremel & file work should take care of it.

Ken, I know how to whittle on metal, I want to know if the flanges that bolt to the head are any wider and thicker, aftermarket intake vs OEM, so once I do a port match, I'll have enough metal to drill for locating dowels through the intake and into the head without destroying the o ring groove, thereby compromising the seal. If the aftermarket intakes flanges are 3/32nd" wider or more, I can do it, OEM, I won't even go there. I can't afford to buy a set, just to find out, I have presents to buy too.

I could just turn some bushings to tighten up the oversize through holes and that would keep me pretty close to the same relationship every time. So thank you Ken, anytime you get around to it is good fer me.