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350D engine into a 300 frame ???

12K views 17 replies 5 participants last post by  theblue300 
#1 ·
any one know if it is possible to put a late 80's 350d engine into a say a 95-2000 300 Fourtrax frame , I think the rear would work out , the front I don't know about , I realize that I would have to use the 350D wiring harness and electrical components
 
#2 ·
never heard of it attempted, i have seen fully welded hand built tube frames for 350D motors and suspension which is probably the easier way to go about it. its going to be a matter of if the motor mounts and shafts line up, and the other thing i could see being a problem is will the head clear the frame? thats a tough build if you ask me honestly.
 
#4 ·
It is possible, Like mac said the t-case has to be rotated. I am in the process of building one and i cut the motor mounting peice of the 350 frame and combined it into a 300 frame. It is alot of work to do just the frame itself but its all about how much effort you want to put into it. It took me a total of about 12-13.5 hours to get the 2 frames cut apart and put together into one.

the 2 separate frames


the one combined frame with a 3.75 body lift
 
#5 ·
#6 ·
What are you doing with the output shaft. It is way too high for the factory 300 swingarm and ujoint.
 
#7 · (Edited)
Thats why i used the bottom section of the 350 foreman frame and welded it into the 300 frame. Plus i would have to make 1 motor mount that way. Along with a 350 foreman swingarm and this huge u-joint set up i have on my blue 300 that looks like this. This joint is about 5/8-3/4 of a inch bigger than the stock u-joint. The only down side is i had to move the swing arm mount over .25 because it was way to big even with the external u-joint design.


Stock next to my driveshaft and u-joint
 
#8 ·
Blue , nice looking work , is the bike up and running yet ------ your swing arm looks good but I would fear it isn't strong enough , I have broken the stock swing arms off the bike and was wondering how you sealed around the output shaft of the engine and the input of the final drive without the boot , the pinion seal alone wouldn't be enough to keep the dirt out for me
 
#9 ·
It is running, i havent been on a ride to try it out though, i think it should be strong enough and if its not then i will have to make it stronger. The differential is packed full of grease so it keeps the water out. The out put shaft on the motor has a seal, its not much different than the side shaft seal so im not worried about that really.
 
#10 ·
Another thing too is i based my swing arm off of one that i know worked the idea came from this one. If i ever get time i was planning on adding 1-2 more braces and then call it good until it breaks or doesnt.

 
#12 ·
I dont know much about was done to that 300 all i know is that it had a big lift a 54% and a 477cc 4 valve custom engine.
 
#14 · (Edited)
No, I think you are confused i didnt buy that 300 i built mine this is that 300.



This is mine




I still need to build a bracket to take up the sag from the front shocks being run at a steep angle.
I built the swing arm that i mentioned earlier because of the swing arm on the tan 300 and i had everything to do it.
 
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#15 ·
Awesome , I like them both , the blue one is real easy on the eyes but I like the tan one better , building a big 300 is on my bucket list ------- what other sites do you go to for info on big builds? --- Highlifter's site use to be nice , had a lot of traffic for the mods I like to see , but since they came up with all the new rules and censorship to make it a Highlifter only sales site it seems to have destroyed the site and it is almost a ghost town
 
#18 ·
I made a facebook just for the honda 300 club. I used the highlifter forums for help most of which i tried to with old posts since hardly anyone is around anymore.
 
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