'96 duke

xj9140 · 02-22-2010, 07:17 PM

Just bought a lc4 duke. Its has a Sudco carburetor on it. Is that stock?? Are they any good?

bajadog · 02-22-2010, 11:03 PM

Those LC4s came with either a Quiksilver (Edelbrock) or a Dell'Orto carb, I think in 1999 they went to the Mikuni BST-40.

All of those carbs above were vacuum or constant velocity carbs. Their slide are not directly connected to the throttle.

The Sudco you have is an after market "pumper" carb. Probably a Keihin FCR.

So someone wanted more throttle response that a CV carb can produce, and paid some bucks to upgrade.

Those Sudco's run around $600 and up.

If you want to downgrade back to a CV, I've got a Mikuni BST-40 I rather not have.....

xj9140 · 02-23-2010, 12:19 AM

Sweet, thanks alot man. This is my first bike. And I am totally hooked now. I have a few issues to work out. My speedometer cable is broken and the electric starter makes a god awful sound. I think its the starter clutch. I took it all apart and all the gears look fine, but I couldn't get the thingy off behind the alternator/stayter. I think I need a puller, from what I read.
Also my clutch is slipping under hard acceleration. Its fine most the time, but when I really get on it after up shifting it slips some. Can I adjust it? or do I need to buy a new clutch? How hard are they to replace? I'm a good automotive mechanic, but haven't worked on bikes before.

bajadog · 02-23-2010, 08:06 AM

I am guessing you have change your oil already (synthetic only, and never one
that states ENERGY CONSERVING). I have had friends with clutch slipping issues when they used an oil with ENERGY CONSERVING (friction modifiers).

The clutch adjustment wheel should be a plastic star right where the
cable comes out of the lever perch.

On my bike, I lay the it over on the right (foot brake side) zip tie the kick start to the frame, take out the fasteners for the clutch cover. The only "hard" part is making sure you put the clutch disk back in the same order you took them out. Take the old ones out in a complete stack. You might be due a new clutch if it's the original (14 years).

xj9140 · 02-23-2010, 09:52 AM

the odometer reads 13210 but don't know how long my speedo cable been broken. What kind of oil does ktm recommend? Thanks for the tip on laying the bike over, I like that.

bajadog · 02-23-2010, 01:08 PM

This is the "official" oil that comes in new KTMs, it is pricey though.

http://www.motorexusa.com/offroad.asp

Personally I use Valvoline Syntec 20W-50, it is the only of their products
that does not include a friction modifier. I've run it in my last 3 bikes, and my
last KTM, my '03 had 14000 miles on it before I did the top end.

Mobile 1 motorcycle oil is good too.

xj9140 · 02-23-2010, 03:18 PM

Quote:

Originally Posted by bajadog

This is the "official" oil that comes in new KTMs, it is pricey though.

http://www.motorexusa.com/offroad.asp

Personally I use Valvoline Syntec 20W-50, it is the only of their products
that does not include a friction modifier. I've run it in my last 3 bikes, and my
last KTM, my '03 had 14000 miles on it before I did the top end.

Mobile 1 motorcycle oil is good too.

What did you do to the top end?

bajadog · 02-23-2010, 08:09 PM

Quote:

Originally Posted by xj9140

What did you do to the top end?

I did the piston rings (KTM), had the head machined (valve seats), and then went with Kibble-White stainless steel valves. Then I rode it in the 2008 Baja 250 and sold it.

xj9140 · 03-09-2010, 06:20 PM

after a few weeks of commuting to work, my air cleaner is full of motor oil. Does this mean I need piston rings?