Getting more out of a 80LF

[motoXman]

I want to make some changes to my gearing and secondary clutch. I read a post on here where stock gearing from a 80+ trailfire 340 really wakes up the 440LF. Can someone here verify to me what the sprocket count is for this machine? And if you have the gearing to sell inbox me.

With the secondary I read to use a 38*/44* dual-slope helix from a Sportfire instead. Does anyone have one to spare? I guess for now I will stay stock on the 102-c and the secondary spring unless someone has any recommendations?

Has anyone tried a trailfire muffler on the LF? I'm wondering if it would have a negative effect on performance, it seems to look like a direct fit except part numbers. Maybe someone here knows the mechanical difference inside the pipe if there even is one?

[cfedorowich]

I would check out the shift RPM for clutching... pretty sure the LF runs a higher RPM... if that is so then swapping to the TF exhaust would be a mistake. CF

[Ryker Carruthers]

The cone in the LF muffler is closer to the engine I believe. It wouldnt make it run better... I had a LF muffler on a TF without even thinking of lookimg amd it wouldnt get abouve 40. The 340 gearing will help with bottom end. Look in the JD tech manual for ratios and tooth count. And the 82 fine tune manual has it too. Some say stick with the stock helix, some say the sporty helix. From talking with a few people and a few threads i would keep the secondary with the engine. I will probably told otherwise though. I was going to put 21/39 gearing (1.86-1) in my 80 but I need a 68 link chain. Those were out of a 440 trailfire.
Ryker

[Kurts]

Enjoy the lf for what it is. If you want to go fast sell it and buy something fast. I bought a 94 wildcat a few years ago for $400, and it's nice. skis up to 80mph. and it keeps going from there. I completely forgot about my eltigre that I loved, and I almost feel like parting with my 295/s

[motoXman]

I have a set of 21/39 gears spare set. I will have to open up the LF and see what I have in there. Nothing wrong with wanting the most out of what I have... And it's working real good BUT there's more there and JD didn't have it all right from the factory. Thx for the replies

[Kurts]

If it were me, I'd gear it to go a realistic 65mph tops. I'd get a FTM, and use it to guide myself. I live in illinois, and all we do is ditchbang, so I don't need 80+mph for lake runs. I'd also be dynoing the engine to see what the power really looks like.

[SIIaCanuck]

Regarding the Sportfire secondary helix, I'd considered the same thing. However, many more experienced guys, on this forum and elsewhere, suggested that just getting the stock setup running well will make a world of difference so I'll pass on their advice and suggest you might want to work with the stock secondary and see if you can get it to backshift the way you want.

I've got both but the stock setting for a LF is hole 2, and that's with a new spring. You can go tighter and/or refresh the spring and both should improve the backshift. If you still don't get what you want, then try the Sportfire helix. The swap takes only a few minutes so there's no real problem with playing with both. The danger with the Sportfire helix, as mention in one of my threads, is that you might end up getting rpm creep on the top end.

Playing with the gearing will probably get you better results.

I discovered my sled had 1.77 gearing (22/39) and I lowered it to 1.86 (21/39 - 440 Trailfire). Fortunately the 1.77 setup uses a 68 link chain so I didn't need to search for a chain. The 340 Trailfire (17/35) setup gives you 2.06 and that may be a bit short for you, depending on what your regular riding is like. 1.86 with a 102c gives you about 88mph on the track at 8000rpm and 2.06 should give you 79mph. Even 1.86 is a big drop from stock.

If you don't care about the top end, then 2.06 might work for you but you might struggle with traction. You could just be spinning the track depending on how much lug/studding you have.

As I say, this is just the direction I'd suggest based on the advice I've had from other forum members.

Can't comment on the pipe, haven't compared the two.

[motoXman]

Did changing your top gear by 1 tooth in the chain case make any noticeable performance gain? I would think you didn't lose much on top end

[SIIaCanuck]

I couldn't tell you as it was running like a dog when I pulled her apart. Too many changes to tell you what the gearing would do on its own.

I chose the 1.86 just because I had it in my work-bench, 1.86 gears are common and easy to find parts for, I'm putting in an 8 inch primary (108EXP) and she'll never pull the top end of the 1.77 gears anyway. She'll be back on the snow with a new 108EXP clutch, re-sprung secondary, rebuilt carbs and a different ignition.

My logic for recommending the 1.86 gearing is that the 1.59 stock gearing and a 102c would net you 103mph at 8000rpm with a full shift. Unless you're running down a long lake or hard-pack, you will never get anywhere near the top end.

Even the 88mph you'd get out of the 1.86 gearing would be pretty bloody fast on anything except smooth hard-pack but you'll have a lot better chance of getting there than with the taller gearing. I stand to be corrected by more experienced forum members but I recon that pulling over 100 with a stock Liquifire is just a dream.

I didn't recommend the 1.77 gearing because it's pretty non-standard and the 1.86 is easy to find.

[deereboy]

I have the 2.06 final (17/35)gears and have my secondary in the 4th hole pre loaded one turn on a sportfire
helix. I live in northeastern ohio and ride in hay fields and trails in the woods.this set up works great. studded track to help with spin .back shifts quick,launches hard, what you lose on top end you won't
notice .you don't have a 100mph sled any way. just make sure you have it tuned and everything fixed
before you start changing anything. that's my 2 cents
deereboy

[Ryker Carruthers]

When you say one turn do you mean a full turn or to the next post back? I have mine in the 4th hole... I tried one turn but as i got half way around the sled started to move and I was running out of muscle lol.
Ryker

[deereboy]

yes it a real chore. but you can do it.i did mine off sled.

good luck
deereboy

[Ryker Carruthers]

About what rpm and how fast are you going when it begins to shift?
Thanks, Ryker

[motoXman]

I made some progress today, installed my new repo temp gauge from NewBreed, tidied my wiring, replaced the voltage regulator and put all new light bulbs , swapped my skis although none of this is relative to performance I did manage to open up my chain case to see what was in there. What I found was 22/35 1.59:1 I thought that was a bit too tall so I switched up to the trailfire 440 gearing 21/39 1.86:1 I did run into one problem however.. The chain was too short to work with my manual chain tensioner so I had to use the trailfire auto tensioner and cover (I hope this is ok) I went for a short rip today and it definitely has some gain right at the beginning then HARD midrange and strong all the way to the top! I'm very pleased!

[Ryker Carruthers]

I ran into the same thing. Find yourself a 68 pitch chain.
Ryker