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I like the front end. Is the spindle finished? It looks a bit weak and doesn't seem to have any trail. Any idea what kind of power can be made with the scrambler? Might need a boost.
Yet Another purpose build
- Thread starter eric82930
- Start date
Hi res version
Spindle not finished, just mocked up to figure out angles and bump steer etc. It has trail, I'll post up some shots from the side when I get a chance. Yea it's no powerhouse, probably going to be pretty gutless in stock form.
Solid Eric! Love it. I'm gonna do the same style front end on my next build. We gotta make it a point to hook up next winter.
Any changes to this build planned for this season? Or just making another one for the 360?
Where do you ride? I'd sure like to see how your build works in person. I'll be on a camso this year bolted to my 380, and my brother has a kx500 with a timbersled. We are in se Washington state and ride mostly in the blue mountains but will be in the cascades too. Always like seeing new terrain.
Where do you ride? I'd sure like to see how your build works in person. I'll be on a camso this year bolted to my 380, and my brother has a kx500 with a timbersled. We are in se Washington state and ride mostly in the blue mountains but will be in the cascades too. Always like seeing new terrain.
I don't think I'll be doing anything too drastic to any of my bikes this year unless the 4 stroke has some deep pow handling issues. The 360 is still on a modified riot and I don't want to butcher the riot enough to ruin the resale value. I might have to sell it, if the vax mandates take hold my whole family will be unemployed. I ride wyo,Utah,idaho. My 380 had just 1 Polaris running board cooler and NO radiators. It was enough but I did have to run the scratches if the road was hard pack.
Yeah I hear you, I may be out of work with the Vax mandates too.
If you had two of the coolers would you run both or still just one on a 380? My camso kit isn't super easy to run scratcher on but I also avoid trails at all costs. Getting to new areas may require some trails though. I'm not opposed to windowing my track and or fabbing some scratcher mounts for the monorail. I'd rather had a TS but I was able to get this 18 camso literally brand new in trade for a sled so I figured it was worth trying.
Also what exactly did you do to your 380 to get from the stock 49hp to 60 plus? I'm considering cutting my stock head in my lathe and setting squish to about 20 thousands. Should I install a spacer under the cylinder and cut the deck too?
If you had two of the coolers would you run both or still just one on a 380? My camso kit isn't super easy to run scratcher on but I also avoid trails at all costs. Getting to new areas may require some trails though. I'm not opposed to windowing my track and or fabbing some scratcher mounts for the monorail. I'd rather had a TS but I was able to get this 18 camso literally brand new in trade for a sled so I figured it was worth trying.
Also what exactly did you do to your 380 to get from the stock 49hp to 60 plus? I'm considering cutting my stock head in my lathe and setting squish to about 20 thousands. Should I install a spacer under the cylinder and cut the deck too?
I would not run 2 coolers - they are heavy. Just use one cooler and one radiator if you don't want scratchers. Just cut the head as much as you can until the metal gets paper thin on the ex cooling passage blockers. Most of mine I could cut 70-90 off. Then raise the cyl with 2 or 3 of the thickest gaskets glued together. Also cut a mm off the top of the ex port and lengthen pv rod a few turns to make sure it's getting full open. Do NOT run the squish at 20 shoot for 50-65. That's really all it needs and you'll be over 60 easy. If it won't rev go leaner on main. I'm at a 145m at 8-12k altitude. CEL needle is a good choice.
Thanks alot, that saves me a lot of time messing around. You have to run race gas with a setup like that? I already keep 100ll around for my sled so it could be an option.
I agree with Eric about the one cooler. It doesn’t take a lot to cool a dirtbike engine.
Haha race gas is totally dependant on how tight you build it. My builds were for pump gas but really close to needing it in the parking lot at 8k zero degrees it would detonate. I have 3 heads of different tunes so I can quick swap on the hill or when tuning I ran the smaller 2k2 fly wheel so I could adjust the stator plate without a puller.
Sounds about right, won't know if you need more octain till you try it. I'm looking at buying a stator right now. Im only getting 6v out of the lighting coil at idle, 10v at 6k. My 380 is a an exc so it has the big 2k-3. I think I'll just replace it with another 2k-3. Trail tech sells a upgraded stator the 08-16 2 strokes that looks like it can be adapted to the older bike.
It started this morning pretty easy after sitting on the trailer all night in -15 degrees. It still has 5w30 in it too. I have a good wrap on it and is been perfect in the deep early season fluff. Power has been way better than I expected from an rfs 450! it's real close to a new fi bike. The light weight great power and big track makes it actually work better than my raptor did in the baseless snow. 40 hours this season and nothing broke yet. The low seat feels a bit odd. more like a sled. And I do ride with my knee on the seat sometimes like an old polaris... it is very comfortable just doesn't feel like a bike. I changed the needle in the carb to an "E" taper and now I have throttle response better than many fi bikes I've ridden. It is almost as zippy as my 2 stroke. Almost... I'm probably going to have to build a frame like this for my 360 with the riot.
Eric, did you get that bigger ball joint installed?
Not yet it's still sitting in my bench cause I've been too busy riding it. The reverse gear project earned its effort 10 fold this week end in deep survival snow. I had to break trail most of the time because if the route terminated early I could just back down my own track and turn out elsewhere. Never got stuck in 3 days. It saved my back and every one in my group too.
This is my current lower joint and is the same as the top joint. But it will be replaced by the new tclamp in the previous pics. They are working just fine but heim joints were typically used as upper a-arms and I don't think they were designed for the direction of force that I'm using them for.
Eric's reverse is nice. When he is breaking trail in tight woods all I have to do is sit and wait. If I can carry momentum pick good lines I can catch up quick. Our backs and googles are happy.
When I used to run the RFS engines I often thought about getting one of those from a quad with reverse. Never did it but I now have reverse in my bike with an 800 Polaris sled engine. Initially I was quite happy with the ease of unloading it from my truck. However, I've been finding the same thing as Eric in that it is quite handy in tight situations.
did you make any progress with the scrambler project?
mine is done except for cosmetic improvements it's perfect. we finally got enough snow i was able to ride it today to test it with the hi low ignition map switch, with the cdi in the high mode, wow totally woke up the mid range. I rode it the whole last season in low not realizing the cdi I got on ebay was new enough to have the dual maps but my wire harness didn't even have the grey wire installed so I never gave it another thought until last week I saw the mfg date on the cdi was 2007 and I had a flashback of the big thing in 07 was the factory dual map ignitions...
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Will be testing it out once snow hits the ground here! Still have plastics/shrouds to figure out, and the heat exchanger..
