6 replies to this topic

[azreider TT Newbie]

I just picked up an '83 ft500 and am looking to ditch the air box and install a K&N type vilter and maybe put on a "performance" carburator. Is there a carb anyone can suggest?

[judgie13 TT Newbie]

i have also just got one of these bikes and am curently rebuilding the motor.
mild porting job, 10.5/1 piston, mild cam.
looking into header design but theres very few out there for the ft so looking at building my own.
carb wise i was told to look for a 38mm flat slide. as for jetting hints i have no idea at present so am in the same boat as you.
company that is doing my cam has run them on anything from a stock to a 40mm lectron.
i have been looking at 250 crf/kxf etc carbs but there a bit out of my price range atm. i'll keep looking.

[Mr. Neutron TT Gold Member]

I'm sorry I'm "memory challenged" right now......   Is the FT500 a thumper?

If it is, I can wholeheartedly recommend a Mikuni 38mm roundslide carb. I had one of these on my XR500 I vintage raced, and besides giving a little bit of boost in power, it is a very easy carb to live with. Starts well, idles smooth, takes sudden/quick throttle openings well (you do have to sorta roll the throttle on smoothly & quickly), & is overall easy to tune. I have some jetting specs, if anyone is interested......

Carb: Mikuni 38mm VM Round Slide

Slide Cutaway: 2.5

Needle: 6DP1, clip in the middle notch

Pilot Jet: #35

Needle Jet: Q-0

Main Jet: #220

Air Jet: #2.0


Hope this helps some!!!

Added in Edit: This was the first VM Roundslide carb I've ever had to change that "Air Jet" mentioned on the last line of the jetting specs. It's the little brass one that takes a smallish regular/slotted blade screwdriver to remove from the "belled-out", or air intake, end of the carb. Sits at approximately 6 'oclock   or so in that part of the carb, and mostly controls idle/low throttle openings, if I recall......
Jimmie

Edited by Mr. Neutron, 23 January 2012 - 02:51 PM.

[huskyfrk TT Silver Member]

i  am  currently restoring one  i  bought  new,  it  has  sat  unused  for  a  good  number  of  years.  i   took  a  supertrap  for  a  fj1100  and  built  a collector  for it, used  the stock  head pipe.   took  the  stock  air cleaner,   cut  the  filter  off,  welded  a  piece of  tubing onto  the  mount,  left  enough on it   to fit  a  slip on K & N  on to it,  so i  had  the  stock  airbox  and  battery  holder.    Biggest  change  was  the  gearing,  it  comes  geared  WAY  to low.    went  + 1  on  the   countershaft,  and  down -3  on  the  rear. dropped  the  revs  at  freeway  speed 1,900  revs, almost  2,000   saves on  vibes  and  engine  life,  also puts  the  motor  at  the  bottom of  the power  band,  makes  for  passing a  lot  easier .  fork  kit  w  HD  springs  was  a must.  rear  shock's   help  too.  installed  a  gunfighter  seat  for  it.    adjustable  bars  from a  nighthawk  worked  sweet  as  well, and  last,  a  Rifle   1/4  fairing.

[huskyfrk TT Silver Member]

if  you  want to change out  the  carb,  i  would  go w  a  37m  keihn, like on  all the  new  4strokes.  jetting  is  easy  to  find,  lots of  tuning info  around....,  but  you  may  have  to  get imaginative  w  the  airbox  or  filter  set  up  if  you do  that.

[bomber737 TT Newbie]

I had one and I put a 38mm mikuni flat slide.  I got it from sudco and it was jetted up almost perfectly when I got it.  I also put a F1 racing muffler on it and cut out the inner header pipes.  Really made a difference with aceleration and top end.

[vernwrites TT Newbie]

 bomber737, on 18 September 2012 - 08:08 PM, said:

I had one and I put a 38mm mikuni flat slide.  I got it from sudco and it was jetted up almost perfectly when I got it.  I also put a F1 racing muffler on it and cut out the inner header pipes.  Really made a difference with aceleration and top end.

Where did you get the muffler? Part number? I got an FT500 late last year...live in Coeur d'Alene, Idaho so don't ride in winter. I'm looking for a bit more performance and a bit more sound (noise?) from it. It is stock and whispers...I'm an old TT guy and not into making a lot of noise, but this thing is too quiet...
I'd appreciate any feedback you have.
Vern
vernwrites@gmail.com