Pursuit of a track Moto (My first track day build)

RowdyRhody

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Once I got to this point I moved onto doing something ive wanted to do for a very long time. In 2018 i had the idea to make the seat frame a sperate subframe. I was unaware at the time that KTM did this in 2017 with the duke 390 and 2019 with the rc390. It would be much easier to buy one of those bikes...alas i have a 2017 that i already own, so I set about designing/ fabricating a rear subframe from aluminum that would bolt to the steel via 4 mounts. I used PVC pipe with similar outer diameter as a 1996 gsxr 750 aluminum seat frame i have that i referenced for material thickness/size to build mine. it worked out really well. During this process i also began sketching and taking measurements to make a reference 3d model to work off of. I want to build an entirely new tail section but also redesign the front fairings to be more of a half fairings style... moto 3 bikes have a completely carbon rear section. my budget/time doesn't allow me to do this right now, as well as I'm sticking with the idea of running a single undertail exhaust and mounting it to carbon seems tricky.. as well as working on the frame mounts so my tail will have this trellis aluminum frame that holds the seat and exhaust up and is then covered by a fiberglass seat that will tie into the rear tank cover as one piece.
SEAT FRAME
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Fuel tank pump mounting bracket needed the filter holding tab removed..

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I cut up and reorganized the 2017 battery tray to fit under the rear tank fairing, plastic welding it back together its pretty solid. This will house the battery/ecu/power commander v/fuses/relays and other various electronics and sits on top of an aluminum plate i cut/bent to fit in.






 

RowdyRhody

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FOAM MOCKUP
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Will probably take me one or 2 more tries to get this seat foam shaped correctly...
 

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RowdyRhody

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SEAT FRAME CONTINUED
Ive never welded aluminum before or fabricated a piece like this but i went for it. Still need to finish a few spots in the tight angle tube intersections and add tabs for mounts/smooth some edges but I'm stoked how its come together... ive wanted to do this for years.
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I think my fat ass standing and bouncing on this thing at the best point of leverage is as good a stress test as any 😂
 

RowdyRhody

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Today i stripped everything down again and gave the frame a half assed paint job along with tabs i extended on the fuel tank...
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There's a lot more that i just haven't written as I'm tired right now and just want to get out the updates. Lots of photos too.. ill probably proceed in this way of mainly photos with a few bold text titles and short descriptions. Thanks for any interest/questions/comments i hope you guys find something interesting in my project. Today was the first track day/racer practice for penguin and NEMRR so I'm a little disappointed that im not there but ill push to make round 2 may 18th... Its been about 3 weeks and I'm happy with the progress I've made.

Adreani front fork kit is sitting on my workbench waiting to go in, im considering a new rear shock.. if anyone knows of an affordable WP or Ohlins please let me know! Formula 390 has a new sprocket setup for the 415 chain/better gearing for my track. Ill hopwfully test the wiring harness soon after cutting out so much and if its good itll get fully wrapped up and in place. Depending on budget there will be some other cool parts going on...
until next time!
 

RowdyRhody

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So far this week I got the engine back into the frame and some pieces bolted up. also realized i didnt have a good photo of the seat frame...20240429_091749.jpg

Unfortunately these super annoying fuel lines kinked on me over multiple times moving the fuel tank so I've got a 2023 set coming, the newer models use traditional rubber with crimp clamps thank god.20240428_162647.jpg

Check this out! I welded closed the radiator thermostat line and removed the thermostat hose setup. Tyga has a clamp on cap for this and a hose for the upper radiator but i went into AutoZone and found this hose that fits PERFERCTLY. left the part number 87858 on there for you guys. Not only does it clear the frame rail and line up with it without kinking, one end is a 5/8" for the radiator and the other is about a 3/4" for the head, like it was made to be!

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RowdyRhody

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So unfortunately i did not make round 2 of NEMRR this weekend but made a good amount of progress this past 2 weeks. Here we go:
SEAT AND EXHAUST
I began by finishing off the rough sculpt on the pink foam seat id shaped and covered it in tape and placed it within the fiberglass tank cover. I then worked fiberglass over it making it one piece. Unfortunately while it set overnight i had not notice the foam shifted at an angle so it became off from center line, Im not overly concerned with that as im not considering this a final seat but rather one i can sit on and ride, ill work towards a final later, hopefully using proper molds and carbon. Breaking the foam core out of the seat was not very fun and i reminded myself it took hours to shape so its a bummer to lose but i know how this process will workout now for future.
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Next, I got to work on making the new exhaust midsection and mounting the muffler. stainless 1.5" tubing, a DB killer inserted into the muffler, old muffler previously used and slip fit pieces all through amazon prime. Front TYGA header I cut off the weird sized connecting section and welded in piece of 1.,5" for slip fit. Fitment is REALLY tight, ill be working on loosening it a hair for less rigid setup (i did use rubber mounts in the center and rear).
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I got everything bolted up, including tank and seat/electrical box and rebuilt the forks with an Adreani Misano for kit (Will do a short write up of installation as i don't see any specific to the rc390), new fuel lines from the 2023 model which now use traditional rubber hoses instead of that hard plastic BS. Exhaust, seat, fluids in, front windshield and fender painted up. front brake pads and pin and cables routed with the system bled. Only to Unfortunately, after working all week on the bike and working thursday from 11-5a.m. friday morning, turn the key to have the dash light up and tell me "CAN FAILURE" . I was bummed but that's what happens with last minute testing. I'm 90% sure it has to do with my complete removal of the abs system, i knew when i cut the module out that it may cause and issue but didn't think id be right up to the final moments before an event to test it. Ill get that wired back in and report here on how it comes together...
 
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RowdyRhody

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WEIGHT:
On the positive side of things, I grabbed 2 cheap scales at Walmart and weighed in the bike. With one Gallon of gas, minus the fiberglass numberplate/windscreen, fork oil and rear brake fluid. Bike tipped the scales at
145lbs/66 kg FRONT
132lbs/60kg REAR

Total: 277lbs/126kg

I'm sure once everything is all said and done (full front fairing, intake snorkels, seat, full fluids) The bike will be around 285lb/130kg

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