LTR jetting informaton

[MikeB]

Now please excuse my ignorance here folks. I have a LTR jetting kit for my MC250 99. I was sent a kit that included a -0 needle and a 42 slow jet, also a 172 main jet. (Middle position as well) My previous altitude was between 5500 and 6000ft. I don’t want to second guess Les but many of you previously said that this was to lean. Now I’m rejetting the bike for 500feet. I was told that I should go up about 2 steps in the main jet. (178) my question is does the new needle (LTR) require the bike to be jetted leaner/richer or the same. Any suggestions (main jet or slow jet or needle position)would be greatly appreciated.

MIKEB

 

[JoshP]

I'm riding at a 1000 feet and I using a 35 pilot and 175 main, which seems to be working good for me. Most I know are using a 40 pilot and a 175 or 178 main. Hope it helps and good luck.

 

[MikeB]

Yes that does help, THANKS.

KEEP IT COMMING!

 

[jeffd]

Hi Mike,

I talked to Les @ LT-Racing (LTR) - he is my best friend from childhood and I talk to him almost every day. I asked him to post a reply to you - but he said he had already responded to you via e-mail yesterday.

I won't tell you what I think you should jet - since I have been accused of spamming for my best friend's jetting kits (yes, I am very, very biased).

I will say that once you ditch the stock needle and get the jetting close at one altitude, then you can use the temperature and altitude correction tables in the back of the manual and it will get you pretty close.


jeff

 

[MikeB]

Once again thank for all the help. I know some of you get tired of the newbees but we really appreciate all the help, time and attention.

So thanks again.

MikeB

 

[JoshP]

Mike,
Don't forget about playing with the air screw, since you are coming from a place with much less air. Your Main (172) should be fine I wouldn't go above a 178 and your pilot go to a 40, keep your needle mid clip and start at 1 1/2 to 2 turns out with the air screw. You should be getting a nice even throttle hit out of that. Good luck with it.

 

[Brian VT]

More ignorance coming. Sorry.
'03 EC300 euro. ignition.
This summer I was running 178, 42, LTR #0 on 2nd notch down, #7 slide, 3 out on air screw, 40:1 Amsoil. Avg. 0-2500' elev.
I'm slow. I accepted a slight sputter off idle and an abrupt cut out of power on the top. I mostly ride low-mid rpms so I was content with it.
I just installed new reeds ("stock" Boysen). The old one weren't sealing quite perfect.
I rode last week and today in 20 deg. farenheit.
I ended up with the air screw at 2 1/4 out and everything else the same. The bike seems to be spot on. No sputter anywhere, it revs to the moon, the plug looks ok (to my untrained eye) and it will idle forever. I didn't check the plug at wot, though. I get scared up there.
Just to experiment I put the needle clip in the middle. It ran like crap and blew spooge out the hose on top of the right side PV cover.
I put it back on the 2nd clip and I guess I'm set for the enduro in 2 weeks.
So, when it warms up in the spring, what direction should I head with this jetting ? My LTR kit said 178, 48, middle clip, 1.5-2.5 out at 60-80 deg. f. but my present settings make me think I'll need to be even leaner in the warm than I am now ?

 

[gasIdaho]

I was wondering why you went with the stock reeds as opposed to the Pro Carbon reeds? I'm getting ready to put new reeds on for the 1st time

05' EC300 - I'm running 168/45, LTR#0, center clip, #7 slide. I'm pretty sure this was set-up to run at 6000'. Much of the year I'm riding 2-4000' in fast desert terrain though so I'm thinking about going up in size on the main jet..possibly 172. I wonder what kind difference I will notice..if any

 

[Brian VT]

I was wondering why you went with the stock reeds as opposed to the Pro Carbon reeds ?

Actually, you're correct. I told my dealer "stock" reeds. I received carbon. They are not multi-level like my buddy's though.

 

[Brian VT]

I guess I can shorten my earlier question.
Is it possible that a bike which runs good on a 42 pilot at 20 deg. can also run good on a 48 pilot at 80 deg. ?

 

[eff]

I'd be thinking more like a 40 pilot.

 

[Brian VT]

I'd be thinking more like a 40 pilot.

Yup. I gotta call Les one of these days though. I gotta believe he knew what he was doing when he wrote 48 and middle clip but I just can't make sense of it (or get it to work) with my limited knowledge.

 

[eff]

I just got the LTR jetting kit, so I'll be testing it this spring.

Granted mine is a 250, but I hope I don't have some of the pilot "oddities" that some of the 300 guys seem to.

 

[JoshP]

Eff is right Brain VT. Run with a 40 pilot and you will see the difference. I have the LTR kit for my 250 but I only ended up using the slide because the rest was way too rich and my bike just bogged around. I'm running with a 35 pilot, #0 slide Mid Clip and a 175 main in all temps with no issues. Seems to run better in the colder temps. I started at stock and got to my current setting so don't use mine as a starting guide (don't need to be fixing more than my own bike!).

 

[wise old man]

Have just returned from the my trip to the U.S.A and while I was in the area I paid Les a visit to get a jetting kit and powervalve cover for my 07 ec 300. Les is a wonderful person and only to happy to have me pick the kit up from him. From new my bike ran pretty ordinary down low and I was interested to see what difference the LTR kit would make. On my return to Australia I pulled the carb off and was puzzled to see a 178 N1EF needle 3rd clip and 40 pilot, As the LTR kit had the needle 178 main and 50 pilot Les also included a 45 pilot because of the splutter down low. This had me puzzled as it looked to me that it could only make my problem worse, but I had faith and installed everything including replacing the 40 with the 45 pilot. I took the bike for a run and all I can say is it was a different bike pulled clean right off the bottom, I pulled the plug and it was sooo! much better looking. I am puzzled as to how the kit fixed the bike and can only put it down to the needle design. I feel I could maybe go back to the 40 pilot but don't know if I should play with what seems close to perfect. Now for that powervalve cover Andrew.

 

[mattmax]

I guess I can shorten my earlier question.
Is it possible that a bike which runs good on a 42 pilot at 20 deg. can also run good on a 48 pilot at 80 deg. ?

No way possible, unless the laws of physics cease to exist when your motorcycle starts up.

I installed the LTR kit on my 05 MC250 without ever trying to jet with stock needle.Stock pilot was a 40, and LTR kit came with a 48. By going to a fatter needle, it is possible to go up on the pilot jet, so I didn't question the huge jump

The 48 smoked and blubbered all over the place at about 1200 ft, 60 degrees F. I installed a 42 and adjusted screw to 1/2 turn. Could have stayed with the 40. I already had the clip at the top of the needle. Ran great, but had a lean spot about 3/4 throttle.

I took needles out and checked with Digital caliper. LTR has same top diam as stock, so pilots will run the same. LTR is straight taper needle, where stock is dual taper. All power valve bikes I know of run dual. Don't know why or how they determine where the tapers should be, or how someone decides a dual taper bike needs a straight taper. Four strokes like multi taper. I'll try both, and decide on my own

I'm going to put my stock needle back in on the 2nd clip from the top and see how it runs. I may even go back to a 40 pilot. Air screw should adjust between 1 and 2 turns, or somewhere close. Don't believe in jet kits, the bike and carb manufacturers should know how to get top power out of their bikes. Bikes that don't run well, don't sell.

 

[GMP]

Actually the N1E series are triple taper needles. I was told the reason for using these needles, with a sharp third taper, is because smaller mains are required. Main jets are available in finer increments as they get smaller, giving greater tuning flexibility. If you ride on the main a lot like in MX, no problem. I like the way the midrange feels with the single taper needles.

You have a different head, and maybe a different slide than the EC. Many variables.

For measuring needles, no way you can get accurate #s on anything but the straight dia. with a digital caliper alone. I've played around with an optical comparitor at work, thats a cool toy.

 

[mattmax]

needles

Three tapers? When I get home, I'll have to look again. I could only detect two, but I was using crude measuring tools. I just wish I could find info on manufacturers numbers.

I measured about a 3 degree taper on the stock needles last 15mm, which would richen up the part I suspect to be lean. I have a #7 slide. From what dealers have told me, the motors are almost identical, except for pipe, head, and flywheel weight(also opposite crank weight).

With a digital caliper, I figured out the LTR letters for my 250. The diam is easy, the other two are interpolated by knowing the value of the variable letters. L1 has to be measured very carefully, or a X could get mixed up with a Y. A basic working trig knowledge can find the angle, you measure the diams and distance at two taper points, and treat it like two stacked right triangles, and calculate one angle using inv sine and multiply by two and hope it comes close to an angle that has a letter assigned to it.

 

[iancp5]

Yup. I gotta call Les one of these days though. I gotta believe he knew what he was doing when he wrote 48 and middle clip but I just can't make sense of it (or get it to work) with my limited knowledge.

Let us know because it caused me no end of head scratching. When I finally abandoned trying to be anywhere near the LTR recommendations I settled on 35 pilot + 2nd clip for my EC300. Somewhat different eh? I also found the standard EF needle on 2nd clip gives a smoother transition.