Intake Query.....

[JetdocX]

I'm in the midst of a fall/winter refit and doing some PM on my 98 Steamer and I have a couple of questions for the guys in the know.

The airbox spits upstream of the filter housing.  One plenum is left and one to the right.  Neither plenum is connected except to the filter housing.  The left plenum has a long duct for air ingress.  The right side has a cap.  WTF?

I've looked at the parts fische and that is all well and good except for:
I look down the intake duct and do the area math then look at three Kehin carbs at full suck and it does not add up.  It seems like the intake duct is smaller than the combined area of the carbs.  Am I even close?

I'm have removed the right cap and I'm getting an intake duct with silencer (filter) for the right side. Anyone done this?  

Thanks.

[aeronca]

not sure why they do that. my '95 has a cap on the left side and i thought about doing the same thing. i read that they de-rated these engines on the tiger's, for some reason, and i figured that they covered one of the intakes to compensate for the reduction of air mass needed. after all they are a super lean running engine. but i would think you could compensate for that by sticking in  a couple of k&n round type filters in each intake hole. even tough it would allow an increase of air mass into the chamber, i think it would actually null it self out through the dynamic nature of a divergant path way through the filter, thus equalling out. same amount of air - beter flow.    in short, let me know if it works so i can do it to :D

[CBAT]

I was thinking the same things as you. I tried it with a simple foam filter on both sides. This created a HUGE flat spot in the middle of the throttle. Bogging like a pig. I put the right side cap back on and all was well. You could probably do some rejetting to take advantage of the additional air intake but that would reduce fuel mileage. I just got back from a VERY dusty week in Big Bend with the additional foam filter. The bike ran good all week but started urging a little at idle on the third day. Once I get done licking my wounds   I'll tear into her and see how dirty things got. I'll report back next week.

[TigerTrax]

Hey guys...
at least on a '98 ....

Leave one snorkle capped. That engine does not run worth a squat
if you unplug BOTH snorkles.

You can switch sides to prolong filter life. BTW: Air filter is good for about 25,000 miles.

Final note:
Removing carbs, messing with the boots, or removing air filter creates
a lot of  issues. Make certain you are careful with the boots and gingerly
reposition them for a perfect seal.

If you have not done so...
follow the fuel line to the 'in-line' fuel filter at the carbs, pull it out, and insert an in-line filter just below the fuel on/off valve.

While you are at it....  clean the fuel valve. Then clean the fuel vent filter in the tank.

[JetdocX]

I'm replacing the intake ducting on both sides of the carb due to age.  I don't trust rubber over 8 years old.  Therefore, clutch and brake lines will be replaced with braided galfer lines, coolant hoses will be replaced and fuel hoses, too.

Good call on the fuel filter, I'll do that.  The fische call out a small inline filter in the fuel line where it meets the hardline at the carbs.  It's probably a finger screen or something like that.

How do you get to the fuel vent filter in the tank?  Back blowing with an airgun?  

Do I need o-rings if I pull the fuel valve apart?

I've already spent $500 on parts for this thing and I'll be dumping another grand or so into suspension.  I hope this bike is worth it.

And FWIW, only two valves of twelve were in spec. I bought that tool, also.

I'll post back with my results.  Too bad I started early on this because the weather has been amazingly spring-like since I took the bike apart!

[Mudhen]

Welcome aboard newbies!  Learn how to use the search button!   :lol:

Only goofing.  GREAT to see some fresh blood around here with the same questions I had not too long ago.  AND...sad to know that the last couple years have gone by so fast - seems like just yesterday I was going through the same thing.

TT will set y'all straight.  Uncapping the airbox requires rejetting, period.  I didn't do my own rejetting work, so can't comment on which jets, etc I'm even running....but I will say that my bike runs awesome since having it done at a local dyno shop.  I'm putting out about 80hp at the rear wheel...I know others have gotten more, though.  Good stuff!!

I run some 2-Bros filters off a 50cc Honda over both intakes...but with mild off roading my K&N still gets dirty pretty darn quick.  After just a few trips and 6k miles, when I cleaned my filter it was disgusting how much junk came out of it.

I also run the stock fuel filter on the fuel tap after two aftermarket inline ones melted on me...resulting in gunked up carbs so bad I had to pull them to clean them out.  I'd like to get a glass one...but until then everything is fine.  I did remove the one down on the fuel line, though...when I was re-running my fuel line down and up, instead of down up over and down like the factory.  I had issues when switching to reserve...it would just die on me.  All has been fine after the reroute.

Pat

[JetdocX]

Yup!  Thought I'd just do something simple and quick today:

Installed a Signal Dynamics LED voltage indicator.  After I connected the wires, I found that the wires I used (spares for the Euro-spec'ed parking headlights) were suddenly dead ie no voltage.  OK, must be a fuse, thinks I.  What else is not working?  Tailights were inop but the brake lights were working.  Sounds like a fuse, except the fuse was OK and the instrument backlighting was working.  SHIT!  

After much disassembly, I found the blue to red wire contact set in the ignition switch was not working and it failed the instant I connected the voltage minder. :idea:   I soldered blue to red bypassing that part of the switch and all is well.  This took me about three hours longer than it should have.

Thanks for listening to my long whiney story.  Ten year old bike...I guess I should expect the unexpected. :roll:

[nightrunner]

Welcome Jetdocx.  Scroll down to my thread in 'Steamers' on rejetting the steamer.   As others have stated, the Tiger airbox is a pinch point and it really shouldn't be IMHO.   I have read where others have gotten rid of the side boxes altogether and run prefilters over the two airbox inlets.  I kept mine so far.  I rejetted and now can run with or without the left side cap.   Have been thinking of some way to put a prefilter in those side boxes.  Stock jetting is extremely lean though.  You'll also find it easier to start if you rejet.

As for the purpose of the cap, I can only guess that Triumph had to meet emissions specs but made it easy to increase the airflow.  Cant think of any other reason for that cap.

When you have the carbs off put a light coat of wheel bearing grease or vaseline on the intake and airbox boots.  Pulling the carbs to clean the filter will be much less of a chore.  

Most of us gearheads remove that little fuel filter as already stated.  I left it in as back up and just added a regular filter ahead of it, below the petcock.  

As for mods, you can also get the Factory Pro ignition advance plate.  The steamers have fixed timing and this will advance it 4 degrees.  Costs about $55 and adds some low end grunt.

Please keep us posted.
Cheers

[JetdocX]

Thanks, Scott.  How difficult is the ignition advance plate to install?

Will I get detonation if I advance the spark that much?  Is it a fixed advance or does it increase with RPM?

[nightrunner]

Its really easy to install.  Just pull the left engine cover plate and remove the nut holding the plate on.  The plates are keyed so only one way to align it.   Its fixed at 4 degrees.

I have not noticed any pinging in mine but have only done one 300-mile ride since I put it on.  I know there are a couple of others on this list who have them and they have no regrets.   Hard to say though just how difference it makes.  For me the jet change was the big gain.

[JetdocX]

I looked at Factory Pro's site this morning and lo and behold, my dreams and prayers to the gods of combustion have been answered.

They sell a jet kit for Kehin 38mm carbs.  $129.

Ours are 38mm right? :oops:

I'm not really keen on advancing the timing.  I think I'll pass on that.  Please let us know how it's working for you after say 5000 miles or so.