lst xxl engine flywheel help

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That’s beautiful truck SV250, what fuel and glow plug are you using?
 
Thanks for sharing your set up sv250, I’ll try that when the shims arrive.
 
Can you post a clear close up photo or two of your problems? I can't picture what your trying to get across.

I had an aftershock back in the day, which was a LST1 more or less, but they ran the same flywheel. I ran an LRP28S3 in mine with +2 gears on the bell over stock from rc-monster as well as a gear flip mod in the trans. I ran normal sized tires on mine. I hate hate hated the big LST/LST2/afterhshock tires. Made the thing handle like a hog. However, there weren't many options for gearing, so I had to spend a bit of money and effort to have a more nimble truck running traxxas 3.8" wheels/tires on it.

I ran it for 3 months with the stock engine and an LST2 pipe and smaller 3.2" zombie maxx tires on it. RPM arms, titanium turnbuckles in the upper arms and later for the front/rear tie rods. It was what I thought very quick off the line and handled really well compared to my revo/savage I had at the time.

Then I put an LRP28S3 in it. Was my first "high end" big block, only surpassed in price a year earlier when I put an OS18TM in my revo.

By the time I got near the "clean running" part of break in with the LRP28, the aftershock two speed locked up on me. Replaced that with the LST1/2/3 two speed.

Shortly after that, I lightened the clutch shoes a bit so it was more snappy off the line:
2007-0715-SWLightenedShoes.jpg


Then it was obvious the LRP28 needed more gear as it was topping out so fast and wheelies were nearly uncontrollable. I got the RC-Monster +2 pinions with the LST1 threaded bell:
2008-0829-ASNewPinionsMonsterRC.jpg


Then I did the gear flip in the transmission which added +1 to the gearing.
2008-0905-2SpeedShaftMod02.jpg


It was quick!
However, I started having issues with the 2-speed again. It kept hopping the flat spot and locking up.
2009-0726-LST2-2SpeedShaft02.jpg


I shimmed up the pucks and replaced the hub a couple times but gave up on it and sold it to someone that ended up putting an LRP30X in it.

I did a myriad of other changes to it, but those were most of the ones I recall that dealt with gearing or the engine install. I did run 4 different engines in it. It had a weird flywheel with the back being really cupped/recessed.
 
Hi olds97, my problem is the clutch bell stick out about 2mm past the end of crankshaft, if I will secure it with the shaft screw the bell will lock up, I got help from other forum and I used the Ofna shim kit, the lst flywheel and collets will hit the carb on nova engine so I put shims to clear it and also Ofna shim kit comes with thrust bearing spacer shim to extend the shaft past the bell, problem solve, thanks for the additional information on your post..????
 
Hi olds97, my problem is the clutch bell stick out about 2mm past the end of crankshaft, if I will secure it with the shaft screw the bell will lock up, I got help from other forum and I used the Ofna shim kit, the lst flywheel and collets will hit the carb on nova engine so I put shims to clear it and also Ofna shim kit comes with thrust bearing spacer shim to extend the shaft past the bell, problem solve, thanks for the additional information on your post..????
No problem. I used a spacer like that on my first bell so I could run 3 bearings vs just two.
http://www.beatyourtruck.com/forum/...bd6373e8b7bab4&p=653630&viewfull=1#post653630
 
The alignment of the pinions (LST uses 2 on the bell) and spurs is pretty tightly dictated as your not really able to move the engine at all to compensate. It's one of those trucks that would probably benefit from a slide type engine mount like you would find on 1/8th buggies/truggies. Probably why they have the concave flywheel. As it is, the LST uses a weird flywheel and flywheel nut. Wish I had better photo's of mine since it was a bit odd. Would have been nice to have for reference at least.

You can see it here:
losi-lst-xxl-454-engine-speed-bell_1_4edac252d7b45af22a17ab76ac32b0b8.jpg


But not seeing it on the crank makes it a bit hard to comprehend. If I remember right, even the bell itself was a bit larger in diameter which would suggest the clutch shoe pins are further out from center than a "normal" bell. I don't know why they did that, but it would mean it would change the proper engagement if you tried using a typical 3 shoe flywheel with the LST/Losi bell as well.

I never really had an issue. I think I had to grind a bit off a carb once and I do know I had to use proper shims behind it on the non-stock engine, as they all differ a bit. Outside of that, I liked the setup because it would allow you to easily remove the flywheel without removing the shoes as the springs for the shoes rested on the raised collar of the flywheel. So, that was nice when I would switch from a winter to summer engine, or want to try a different engine out on it. Granted, changing shoes isn't that big of a deal, but it was nice not fighting with it.

The one thing that did kind of suck on this setup was the leverage the pinion put on the outside bearing, as that was 1st gear, which is where your torque came from off the line, so a lot of lateral force on that bearing. Which is why some did a 3-bearing mod with one of those shaft collars/extensions to help the bearings last a lot longer.
 
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It's one of those trucks that would probably benefit from a slide type engine mount like you would find on 1/8th buggies/truggies.

Unsure if TLR does make something similar to this...but does it have to be TLR? I mean an engine block is an engine block, no? The idea is simply to secure the engine, so....just a thought, I....dunno. I run Mugen parts on Tamiya, X-Ray on TLR, Hobao on Mugen, Serpent on XRay, Kyosho on HPI etc. Whatever works. I can no longer keep up. A bell is a bell and a mount is a mount to me these days. Literally,. I don't even store parts by make anymore. Either it fits or it doesn't.

Regardless all of the items I listed in my post above are agnostic of make...so if it's a matter of 1-3mm that is how I would approach it. Yes, bells can vary slightly in diameter, but where they vary greatly is wall-depth...and that would have a greater influence on end-float...so I've learned, anyway.
 
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Unsure if TLR does make something similar to this...but does it have to be TLR? I mean an engine block is an engine block, no? The idea is simply to secure the engine, so....just a thought, I....dunno. I run Mugen parts on Tamiya, X-Ray on TLR, Hobao on Mugen, Serpent on XRay, Kyosho on HPI etc. Whatever works. I can no longer keep up. A bell is a bell and a mount is a mount to me these days. Literally,. I don't even store parts by make anymore. Either it fits or it doesn't.

Regardless all of the items I listed in my post above are agnostic of make...so if it's a matter of 1-3mm that is how I would approach it. Yes, bells can vary slightly in diameter, but where they vary greatly is wall-depth...and that would have a greater influence on end-float...so I've learned, anyway.

I'm not quite sure about other brands ,but a lot of parts I have are Ofna brand ,the engine mounts are versatile as
they allow for adjustments back an forth ,then you have the slotted holes on the chassy to adjust gear mesh.

I like the threaded bells for adjustment to in line each gear .with spacers if needed ,Ofna makes a good variety of
bells ,gears ,an clutch shims!
 
The Ofna Ld3 RTR came out with a size 12 engine ,My Ld3 was converted to a B-block hyper 21 ,
I used the original clutch 2 spd threaded clutch bell with 3 shoe fly on the 21 size engine!

The fly wheels can vary in sizes in diameter ,usually for starter boxes ,but I don't use that ,so I always
try to stick with the smallest diameter ,an the 3 pin fly's to run 3 shoe ,I run 2 aluminum shoes with
one composite for a wiper on the bell!
 

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