Part 9
Steve's been very busy and I'm doubtful I should push
Jack Lilley's more on the setting up of the bike; fine tuning will have
to be done in Hong Kong.
K&N Air Filter
Element for Legend
Meanwhile,
I use the Internet and contact Motorcycle Accessory Warehouse to try to find the K&N element to go inside the Legend
airbox and correspond with Miles Hunter of Thunderbike in New Zealand.
K&N Powersports.com
Motorcycle Accessory Warehouse
(Be very
careful if you use this company to check and confirm their shipping and
handling charges, which they use discounted prices to mask!)
Thunderbike
To
Motorcycle Accessory Warehouse:
A-Fri 11-05-2001 16:28
Do
K&N do, and have you got in stock, a K&N air filter element that would
fit INSIDE the Triumph Legend TT air box, to replace the OE filter element? If
you have, I'd like to order and have shipped to HK.
MAW-Sat 12-05-2001 4:11
Thank
you for your interest in our company. When you say inside are you asking
about a stock air box filter??
A-Sun 13-05-2001 21:22
Further
to my last, I've now found out that the part I'm after is K&N element,
#TB-0004 - for Triumph Thunderbird. Do you
have or can you get them?
MAW-Tue 15-05-2001 6:33
Thank
you for your interest in our company. However, we do not carry the TB-0004. We
have the TB-0002 and TB-0005. Please let me know if I can further assist you.
To
Miles:
A-Fri
11-05-2001 16:36
As
you know, I'm getting a new Triumph Legend TT, revamped as an Ascot TT from
Jack Lilley's and then having it shipped to Hong Kong.
However,
we still haven't come to a satisfactory result with the air filters. I like
the Ascot side panels, mounted on the Triumph OE air box. I've got Keihin FCR
flat slide carbs fitted and they need (so I've read in the lists) a smooth
airflow. This is another reason for me keeping the air box and it's connection
to the auxiliary air box chamber.
Steve
Lilley is going to send me K&Ns with the bike, but only the big ones that
hand on the bell mouths of the carbs. I'm not sure that Triumph Legend carb
rubbers are up to supporting the carbs and the K&Ns without more support.
Question
1: Do K&N do and have you got in stock K&Ns that would fit INSIDE the
Legend air box, to replace the OE filter element? If you have, I'd like to
order and have shipped to HK.
Question
2: The flat slides are coming out to HK with 150 jets fitted. The Ascot
exhaust system is 3 into 3 straight through (great sound!). With the OE air
filter I suspect this will be too rich, yes. Steve's sending 145s also. Will I
need even smaller ones, or in your experience, will the fitting K&Ns cure
the over rich mix by providing a more free air flow?
MH-Sun 13-05-2001 7:46
Good
to hear from you again, I would have got back sooner but spent most of the
night lurking on your Website :-) You have one stunning bike ! I like the
way the oil cooler worked out, practicality aside it's a nice
"custom" touch
as well.
I'm
not sure that Triumph Legend carb rubbers are up to supporting the carbs
and the K&Ns without more support.
This
shouldn't be a problem, we've had the FCRs on three bikes including a dirt-track
racer and the rubbers hold up fine.
Do K&N do and have you got in stock K&Ns that would fit INSIDE the
Legend airbox?
Oddly
they have had one listed for years (#TB-0004 - for Thunderbird) but I've
never seen or been able to get one. I contacted the NZ K&N agent yesterday,
they do not and never have had one in stock. I've had enquiry's on
these from other countries as well so assume nobody can get them. Keihin
make
filter adapters to replace the intake horns (is Steve supplying these with
the filters ?)so it may be possible to fit three individual filters in the
air box but it would be a nightmare fitting it all up to the bike - there's
very little room to work in that area.
Steve's
sending 145s also. Will I need even smaller ones, or in your experience,
will the fitting K&Ns cure the over rich mix by providing a more free
air flow?
A lot
will depend on the pipes (whether they actually work or just sound good).
The record keeping form our dyno sessions leaves a bit to be desired but
all the bikes had 3-into-1 extractors and air filters - main jets around
125/130
seemed to be the norm. The guy who did most of this isn't working with
us any longer so when I can contact him I'll find out if his memory is better
than his record keeping (he is still running the racer mentioned above).
No
air filter - including K&N - will make an engine run leaner. K&N's
high tech
guff sounds good but they forgot to tell the dyno or flow bench about it.
They possibly reduce intake turbulence but they will still restrict the
air
flow. We've tried their stock replacement element on Speed triples (yes-they
did actually make that one) and the difference was hardly
noticeable
although washing out the oil does help flow. Individual filters seem
to work better but I suspect that's because the Triumph air box is too small,
also 3 individual filters may have more surface area than one big one.
I've never calculated this all out, shouldn't be so lazy. If you like the
look of the standard setup I'd try it with the standard filter element fitted
and see how it runs, a "still air" box is an advantage if it has
enough volume.
A
final thought on this, bear in mind that the mains will only start affecting
fuel delivery around 2/3 throttle and won't be "full-on" until
3/4 -
if you mark off the throttle positions on your twist grip you may be surprised
to find how little you use that range. I'd think the slow and needle
circuits would be the ones most likely needing fine tuning.
I
hope this is some sort of help to you, sorry for being long winded - I love
modifying bikes and once I start on the subject you can't shut me up! I'll
get back to you when I can get some more information on the FCR jetting.
MH-Mon 14-05-2001 19:30
I
would recommend running it on Mobil 1-Racing 4T oil when run in.
If I
can help with any other information on these just let me know, they're my
favourite of the carburetted Triumphs. Also
I contacted Keith about the FCR jetting today and his memory is as bad as
his record keeping. He'll take a bowl off one of his carbs and let me know
what he's running. He did say though that the kit was very well set up as
supplied and he hasn't had to change it by much.
Fitting
the K&N Air Filter Element
Found
some interesting previous posts on modifying the K&N air filter element to
fit the Legend airbox in the various
Triumph lists:
(1)
"I've
only read the instructions so far, and there's a tiny bit of work
to
be done on the existing air box (cutting some tabs out or something).
K&N
say the Triumph airbox is quite delicate and probably will not last
as
long as the K&N filter but
using the OEM part is required."
(2)
"I
have the K/N "OEM" replacement filter in my bike. I had my dealer
install
it as it requires removing the airbox, and I 've tried that *once*
and
won't do it again. There
are some tabs that need to be cut, and then the new filter is set
in place. You should use some silicone sealant around the edges."
(3)
"Yes,
cut the tabs out a bit as per the instructions to give the K&N sufficient
space. The dealer didn't do this to mine initially, and they
didn't
take care how they assembled the airbox, either. The filter was not
seated
properly, in fact it was caught between the two airbox halves, stopping
them mating together. When the screws were tightened, it either
cracked
the airbox or stripped the threads!!
"The
K&N has a soft rubber edge, designed to be compressed laterally to form
a
good seal against the inside of the airbox. When seated properly in one
half
of the airbox, the filter appears too wide and bows up in the middle.
This
is a good thing! The trick is to fit the other half such that K&N doesn't
dislodge itself and end up trapped between the mating surfaces - it
sits
inside these. You'll know when it is right; the airbox will sit firmly
closed,
plastic against plastic, with the edges all parallel under little
pressure.
Only then attempt to fit the screws. My airbox is now firmly and
neatly
closed, even though the two outer edge screws and some others are
missing.
Previously, even with the screws in, albeit already stripped, the
airbox
was bulging apart at the ends and various other places.
"Oh,
and you are supposed to run a bead of RTV silicone around the mating
surfaces
of the airbox halves. I didn't do this, and it wasn't done initially.
During the first few rides, a lot of oil drips out of the airbox
onto
the engine around the sprocket area, and ends up in a puddle on the
ground.
Very disconcerting. The silicone will probably keep this inside
the airbox.
(4)
"Yep,
you can put a K&N inside the airbox. I did it. The K&N 91-96 Speed triple will fit. I used this filter
but modified
the size (of the filter)"
to
which I asked:
A-Tue 15-05-2001 21:37
What
was the degree of modification you had to do to the K&N filter element?
Have you had any problems with the integrity of the stock airbox. Some people have written about it not being
strong enough to hold up. Did you use silicone to seal the airbox after you put in the K&N element?
Do you remember the part no. I see there's a TB0002 and TB0005?
and
got this reply,
"I
can look at the box for the part number. I'll take some pictures the next time I pull it out. I took the filter and lined it up with the airbox, then cut about 2 inches
out of the middle of the filter. Leaving enough to overlap 2 folds of
the filter. Then modified the rubber on the ends of the filter to fit and
used silicone to seal/glue the filter together the filter is still removable/serviceable. The airbox is entirely overbuilt, I just bolted the
airbox back together. I even cut an extra hole in my airbox for more
air. YOU WILL HAVE TO REJET, no question about it. My seat-of-the-pants dyno
and the wheelie ability tells me it worked.
I heard rumours than K&N was going to produce a filter for this
application, don't know.
Maybe the TBS airbox will fit the current K&N? I know from experience, the
91-96 triple airbox will fit the K&N."
Conclusions
re K&N Air Filter
My conclusions
based on the above information:
(1) There is
no specific K&N filter element for the Legend airbox.
(2) It is
possible to fit one from another model, although the work involved may not be
worth the effort since the extra performance gained is only marginal.
(3) I will
keep the stock filter element at first.
Tuning FCR
Carburettors and Air Filters
I do some research into the tuning
possibilities that come with having Keihin FCRs and K&Ns fitted and
read about how much fun I can expect to have.
A-Tue 22-05-2001 2:21
I was very pleased with Miles (thunderbike,
nz) contribution. Although I've found a source for the K&N filter
element, I won't bother with it, least not until we're doing the set up here
in HK. Miles
mentioned Keihin FCRs coming with filter adapters as an alternative to the
bell mouths. Did they?
S-Wed 23-05-2001 1:06
It
might be an idea to get one (element)
as soon as you can, they are not generally available. You
get the full kit (filter
adapters with the FCRs) in the box of goodies!
A-Wed 23-05-2001 8:44
OK,
I'll do that then.
Ah!
The pleasures of discovery, you see I only know what you have time to tell me.
And how much I've got to enjoy when it all arrives. I've just been reading
some stuff on the effect of the Keihin FCRs (in a Ducati tech site) and if
they are as good as people say there it's going to be really fun!
"Got
the carbs installed over the weekend. couldn't wait to try them out. in a
word, FANTASTIC! all I ever wanted to make my bike complete was second gear
wheelies. Now, no problem. Love it. Thanks."
"HOLY
SCHMIDT!!! You weren't kidding about the FCR's! I rode it home last night and
still cannot believe how much different the bike rides. I mean, it is an
absolutely different bike. It sounds different at the exhaust (much throatier)
and the new "whoosh" noise from the carbs is also very cool. It was
pulling so hard when I took it out last night I had to take it out on the
interstate to see how hard it really pulls. The FCR's are MUCH better than I
had anticipated. I feel like I have a brand new bike. Thanks for the kit, it's
all that and a bag of chips!"
"I
just wanted to tell you that I installed the FCRs the other day and WOW! They
work just like you said...I'm very impressed with them."
"You
get the big grins from all of the increased torque. Since the carbs come
slightly rich (an appropriate conservative setting), a few hp can be found
with some dyno tuning. You may not feel it much though, as dyno tuning won't
help torque too much - it's already a lot higher than before.
"If
you want to diddle with your carbs, here's a useful tuning
guide from Factory Pro.
"A
lot of useful tuning info is also in Sudco's catalog:
"I
forgot to mention that the FCR kit helps the bike everywhere. The FCRs are
such good carbs that they will sustain an idle as low as 600 rpm! I still
keep mine at the factory recommended rpm so it'll charge the battery. The
FCRs let you ride like a Jap lighter bike: bring the revs off of idle
slightly and let the clutch out. The FCRs reduce the low rpm stall greatly
and dramatically improve drivability.
"Power?
You can whack the throttle open about the time you cross an intersection and
have the front wheel 4 feet off the ground before leaving the intersection.
"The
only negativity I've discovered is lurching when putting along in 1st gear
under 2000 rpm and trying to cruise at a steady speed. This driveline lash
is pretty common but the quick throttle response of the FCRs amplifies it
slightly.
"Fuel
economy does suffer a bit, though I still get over 40mpg even when in fast
street riding.
"From
idle to 1/4 why does fuel (just a little bit) spray into the air box? The
spray is from the power pulses that transmit upward. FCRs dump serious fuel.
The accelerator pumps shoot streams of gas into the throat. Also, FCRs
aren't meant to be horsed at a stoplight (or on the lift). To put that fuel
to work, you need to be under a load and riding the thing. I can be idling
at a stop and kill the engine by whacking the throttle open.
"With
no choke, how do I start my bike when it's cold? This starts with ensuring
that your idle is still set to 1200 rpm (when warmed up) as recommended by
the factory. Before starting, give the throttle a twist and let it shut. The
accelerator pumps will throw extra fuel in the intakes to help richen the
mixture for starting. You'll need to experiment with say, a short 1/4
opening or opening to 1/2 or full v. two squirts. Don't go crazy, eh? Some
folks also find that they need to also give the throttle a slight touch when
starting to help the revs come up. Basically, it's "feel" thing.
What
about midrange? I've heard that FCRs kill midrange... This is misinformation!
The whole reason that this "wives tale" came about is from when
FCRs were first introduced on the US market and people put them on GSXRs and
other 4 cylinder Japanese bikes. Instead of calculating the best size for
their application, they'd put 39s or 41s on a street 750 motor, when 35s are
appropriate! The larger the venturi, the less velocity and the less torque.
ducatitech.com
ducatitech.com
S-Thu 24-05-2001 23:44
You
might want to try taking the airbox off at some point and then run with
the 3 x K&N filters, I reckon then you will be
quite surprised.
A-Sat 26-05-2001 10:32
Apart
from the look, which I suppose I could get used to, some people say losing the
airbox / air chamber will result in loss of smoothness or low end torque due
to the loss of the still air capacity. Any comments from your experience?
S-Sat 26-05-2001 16:41
Since
the airbox is not the best design in the world I would hesitate to agree
with that. The open filters work reasonably well in most cases, although
I would bow to those who have tried it and can
confirm that.
Steve
got some more information from Franck at Mecatwin on jetting the FCRs.
S-Tue 03-07-2001 15:32
One
thing about the jetting, Joe fitted 150 jets and raised the needles, speaking
to Franck on my visit there he thought that they may be a touch too small and
reckoned on going to 158. The only snag is that we do not know how the filter
will effect this, I would be inclined to run it with the jets fitted for a
time. If it spits back though the carbs a lot on warming up then start going
up in size. I'm afraid we are all in the dark a bit with it so sorry your
"man" will have a little bit to do.
K&N
Air Filter Element Part No.
I
wrote to Motorcycle Accessory Warehouse (MAW):
A-Wed 23-05-2001 8:49
I'm
not sure which of the TB-0002 and TB-0005 come closest for the Triumph Legend
airbox. Can you tell me? If you can't find out, then ship me both and I could
return the one I don't need?
MAW-Thu 24-05-2001 1:07
Thank
you for your interest in our company. However, I do not know which one
would come closest and which one would work in place of the one you need.
The best thing to do is to call K&N for their recommendation. You can
reach them at 909-826-4000. If you order both and return one you will have
to pay the return shipping plus a 10% restocking fee, so it is best to contact
K&N before ordering.
And
also to K&N:
A-Thu 24-05-2001 6:45
Understand
the TB0004 for the Triumph 885 cc Thunderbird / Legend is not available.
Have
people in the e-mail lists / clubs who have modified TB0002 or TB0005 for the
Triumph Legend, i.e. the models intended for other bikes in the Triumph range.
Please advise which of the TB0002 or TB0005 comes closest and would require
least modification.
Unfortunately,
K&N's staff weren't prepared to say. I got a standard reply that all parts
are model specific to comply with emission conditions etc. and they couldn't
comment on modifications! I ordered the earlier one from MAW, part no.
TB-0002.
A-Sat
23/06/2001 11:37
I've
ordered a K&N filter element for inside the air box - TB0002 from Motorcycle
Accessories Warehouse. Keeping my options open on that one, as you advised.
Continue
....
