My latest build, another trx450r conversion

[Louis Mielke]

Well this build thread is going to be a little bit different than a typical build thread. I've been working on a trx450r quad conversion for one of my good buddies, Jeff and I've finally finished this build in it's entirety and it's owner has happily taken ownership of it.

Instead of trying to recall every little detail and explain the build step by step I'm going to use this thread as a chronological photo dump. Some of the build did not get photographed but enough of it did that I don't think there will be any major gaps. Also, this thread is primarily focusing on the frame build. I have built several front ends in the past so I'm not really going to focus on that. I may end up making some comments about what I'm posting but mainly I just want to show what I did piece by piece, I don't intend for this to be an in-depth build thread.

As a forward I want to mention that I'm not a professional fabricator, nor am I a professional atv builder. I build these things in my spare time for fun. I've only been tig welding about 2 years now and I have plenty of room for improvement. In fact there is plenty of room for improvement in my all parts of my builds and I'm very happy that i can learn and improve with every build I finish.

This is the second 450 conversion I've completed, my first being a collaboration with Jake Keister. We learned a lot building my first 450. He builds some excelent machines but I ultimately wanted to build one completely on my own and I feel this thread represents my success in meeting my goal.

Here's a pic of my first 450.



Here's a pic of the one I've built for my buddy Jeff.



Stay tuned.

[Louis Mielke]

Well I would hope this is already apparent from the first post but this build started out as a 2007 trx450er. Electric start 450 with the kicker added. We stripped Jeff's quad, sold a bunch of parts and I started dissecting the frame, in fact I had another frame so I dissected two and have another back ground build started so technically I'm building two frames at one time. I turned a couple of inserts on the mini lathe to act as joining slugs so the joints will be butt welded and have the plugs welded in as well. I also tried to salvage the stock gussets that are welded on the bottom side of the quads frame rails. I cut them at the welds and folded them back so I could use them again later to tie the new rails together by yet another means.

[Louis Mielke]

Mount one of the diseccted frames up in my jig and mounted in a blown up engine I have been using for mock up purposes.



I've used this jig several times now and I've gotten pretty good at squaring and centering up things where necessary.



Used my tubing bender to bend a couple 180* hoops out of which I cut various curves out for various parts of the frame.



If your curious other than a few small pieces I've purchased chromoly for most of the material on this build





I'm currently working on having a batch of head tubes machined for future builds but this particular build utilizes a 01 CR500 head tube I salvaged from a donor frame. Here you can see the begining of fit up of the down tube from the headtube mounted in the jig.



Here's where the front lower frame rails curve and attached to the dissected quad frame.



This is what I'm calling the mid rails for lack of better way to put it. They attach to the downtube with another section of square tubing.



The general shape of the frame is starting to shape up here.

[Louis Mielke]

Don't pay too close of attention as this changed several times but I was working on fit up here.





Fast forward a little I was happy enough with what i had to firm up my tacks with some solid welds.



Time to work on the upper frame rails, or spars if you want to call them something fancier. Did a lot of bending and shaping and scraping of these pieces. Started over several times until I was happy.













Realy trying hard to make fitup work well with these stock pieces of the quad frame.

[YTZ drew]

Looking great, Louis! Keep the pics coming!

[El Camexican]

Very nice!

Is that a store bought jig? If so where did you get it?

How does that work up there if you make a steering neck with no ser. #, do you stamp something in, or register it somehow as homemade to show you didn't grind the numbers off? If I had something down here like that and got stopped while trailering it they accuse me of removing the numbers and take it away (or at least charge me money not to).

[Louis Mielke]

This was an idea for a brief time but ultimately it changed dramatically








I slowly moved towards trying to make this bend into a longer piece instead of multiple pieces.

[Louis Mielke]

Things started to realy speed in the right direction from here. I bent these upper rails in single pieces and then cut the tail off to serve as a gusset.





I also tried really hard to section out the kicker area. This was actually pretty tough.







This is where my plans for tying the upper rails into the headtube started to realy shape up.

[Louis Mielke]

By this time it was about where I needed to put the bike on 3 wheels and make sure everything was fitting up nice before I really went to town welding everything solid.



Lots of measuring and comparison and notes were made at this point.

[Louis Mielke]

Some changes were made in the head tube angle from the previous pics as I just wasnt quite satisfied with it but I got things how I liked them and proceeded!

I needed to get these gusset plates in before I could realy figure out the radiator mounts.













Mounting these up correctly took several tries and much frustration. Some of the pictures you'll notice things are off and arn't lined up correctly. These rad mounts were tacked and cut loose several times.

[Louis Mielke]

Things start getting fuzzy as to what was when so here's just a bunch of pics.

[Louis Mielke]

So the details started coming togther. First was the front tank mount. It may look a little goofy but I wanted the tank positioned specificaly where I have it so I ended up making a custom front tank mount instead of trying to use the CRF tank mount.

[Louis Mielke]

rear tank mount





figuring out hoses. Instead of buying an expensive crf water pump cover that redirects the coolant spigot I purchases a couple preformed heat hoses until I found a shape that would
clear the exhaust.



coil mount



shroud mount/ petcock mount

[Louis Mielke]

Some more test fitting. getting closed to finished



reshaping the wiring harness



how heavy is it? I don't really know. lol



Finished frame!



Look! All done!

[Louis Mielke]

Found the jig on a chopper site. Small company that makes them so technicaly I guess it's store bought. I'l have to research the website again to find it. I'll PM you when I find it.

As far as VIN numbers I've been using the quad VINs and welding them to the frame after fabrication is finished. I haven't been stopped and haven't had any problems otherwise. I did go out of my way to call the state police and explain what I'm doing and I was told for ORV moving the vin is not an issue. I know sounds nuts but I left it be at that.

Very nice!

Is that a store bought jig? If so where did you get it?

How does that work up there if you make a steering neck with no ser. #, do you stamp something in, or register it somehow as homemade to show you didn't grind the numbers off? If I had something down here like that and got stopped while trailering it they accuse me of removing the numbers and take it away (or at least charge me money not to).