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Discussion Starter · #1 ·
Not for sure this is in the right place but I'm sure I will be told if it isn't. This is a thread started because I could not find any Information on the web showing what I am going to do. This is a 90 something Polaris sportsman 4x4 300cc or so that the engine was blown on. The trans and running gear seems to be fine so I looked for an engine to make this thing go. What I found is a honda cb1 400cc inline 4 cylinder. This engine is capable of about 14,500 rpms has a six speed tranny and was a fun little bike till it was wrecked. Sad that the bike got wrecked but I got an engine for the 4x4 anyway so it all works out. Here is what I have got so far: Streched the bottom of the frame 12" to fit the engine in and a couple engine mounts welded in. Not bad for an afternoons worth of work. Lots more to be done though. What I want is for it to look as close to normal as possible and the 4 wheel drive will still be usable. This quad is all time 4 wheel drive with hi/lo/reverse plus now 6 speed tranny. I want it to be able to crawl in 1st and low. and cruise way to fast in 6th and hi. In hi I plan on never probably taking it out of 3rd or maybe 4th. The atv originally had a cvt set up. This is a great design but It doesnt easily work with what I am doing so I have a plan to put a sprocket on the transmission shaft and driving it via chain just like the motorcycle did only instead of powering the rear wheel of the motorcycle it will power the atv's tranmission.
 

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Discussion Starter · #2 ·
Got a little more done

Today I finished getting the engine mounts welded in and finished welding the top frame back together. Installed clutch lever and thumb throttle(which may be changed to twist throttle ie: motorcycle style):dunno:.
 

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Looks pretty cool with that honda motor in there. How do you think the frame will hold after being extended 12 inches? Good luck with it, want to see what it looks like when its done.
 

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Discussion Starter · #4 ·
I used 3/4 inch solid steel for the inserts on the frame then 1" squre thick wall to extend the frame the engine is also a stressed meber type so the engine actually becomes part of the frame. I think it will hold up nice. I don't know how it will do on log crossing though with an extra foot between the wheels.
 

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Discussion Starter · #5 ·
Got it running

Well I got the wiring sorted on saturday. The thing started right up. I need to work on the carbs because 1 is pouring out gas but all in all it is working to be a pretty easy build. I got the shifter mounted and it works like it is supporsed to hi lo and reverse. welded up the exhaust. and got the front 4x4 hubs wired so that it can be locked into 4 wheel drive at anytime. Mainly all that is left is the cooling system chains and sprockets and stretching the body and paint. I am thinking black bedliner.
 

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Discussion Starter · #6 ·
Got some more done but things are slowing down. I have to get 2 520 idler sprockets 1 for a tensioner and 1 for the front chain to clear the engine. I need to get one more sprocket for the transmission I just have to figure out how many teeth. I have started on the body. I have the lock in hubs working a key switch and a push button start. I hooked up the shifting mechanism to the motorcycle trans the other day. Mainly all I have left are the sprockets, body work front brakes and a fuel tank. I already have the cooling system plumbed and filled and cooling fan works perfect. Not much left just gotta bite the bullet and atually spend something on it. chassis will be done with at most $100 more dollars. All in all I dont have hardly anything in this build and I hope it impresses me. If not I'm sure someone will want it.
 

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Discussion Starter · #8 ·
Got to ride it today

Finished my first trial of sprocket ratio. on my new hub that my friend down the road machined for me. It worked but way to slow...back to the drawing board....
 

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Discussion Starter · #9 ·
i havent abandoned it just been busy

The project is still on going I just havent had much time. I picked up a little vw beetle started on it, now I picked up a gs1100 powered sand dragster atv with full aluminum frame. Soon as i get it going I'm going to try to get back to the polaris/honda.
 

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This is pretty cool. Pretty interested cause I got a sportsman 400 2 stroke and I have little interest in rebuilding the motor so down the road it may be a possibility. What kind of welder are you using? I always wonder when I see engine swaps because I assume a mig would work best and that a stick welder (arc) would have problems with burn through. I am a competent welder but definitely no expert.
 

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Discussion Starter · #11 ·
welder

its a lincoln weld pak 110 volt wire welder. Its a flux core welder with capabilities of gas sheilding but I dont have the gas for it. I can weld all sorts of metal with it.
 

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Discussion Starter · #13 ·
Wish I could tell you it does great but I haven't been back on it since my last post. Life has gotten crazy. Wife had a baby we bought a new house been getting it going.
 

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Discussion Starter · #14 ·
i should be kicked in the butt

I just reread everything from start to stop and I have not mad any progress since the last post. The polaris has just been sitting in the back of the shop collecting dust. I really need to get back to this. I just sold my "around the house atv so this one defineatly needs to get going. I have the idlers and new transmission sprocket i just need to install them mount a gas tank and see what it will do.
 

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cool project!

I guess the sprockets will be guess work until you narrow it down. No manual on this one! lol
I hope you get the beast going and post more pictures, good luck!
 

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cool beans!
just some fyi; if you find it lacking in torque i believe the cbr600 f3 is dimensionally the same or close.
i'll be watchin this. thanks for the write up! keep it comin please.
 

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Discussion Starter · #17 ·
I wish I could get motivated to get back on this thing again. I started on it a couple months back but the sprocket I bought for it was the wrong spline size. Its pitiful really just sitting in the corner covered with dust and other small projects. I have a few paying customers to get done first and then maybe I can get this thing out again and put that 11 tooth sprocket on it and see what it will do. I'm hoping the 11 tooth will work because that is the only sprocket that will directly slide onto the trans shaft. I'm not looking for crazy speed or anything but too fast to ride in 6th and hi would be awesome. low and 1st crawling is my goal. 6 reverses will be crazy. I think the 400 will do good it is what I could find for a easy/cheap trade and it runs/ran great (been sitting far too long. I did start it up not too long ago when I was going to put the sprocket on it it leaked a little gas out of a couple carbs but did start and idle and rev out like it should so a light carb clean and it will probably run golden.
 

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Discussion Starter · #18 ·
Its been over a year(or 2?) since I even messed with this bike but today, today I got to ride it again. The 11 tooth sprocket did work it just took me this long to get back to it. I got it in 4th and about half throttle before I had to shut it down do to space restrictions in my ditch at the shop. I think I was going about as fast as my old polaris 400 used to go stock(no speedo or anything to confirm and I can remember what gear I was in but I know it wasnt 6th). All in all I am happy with this configuration enough to go ahead and finish the polaris on out. I will try to get it back in the shop a weekend at a time and finish the mechanical and redo some things I done when I didnt have a mill and lathe. Then on to body work and aesthetics.
 
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