View Full Version : Big red 250 swingarm swap?
TRE8815
04-09-2016, 05:16 PM
got a big red 250 and am weighing options on wich route to take, I read that a swapping to a trx300 swingarm gives an extra 2 inches in length and better clearance with fabbing up a bracket relocation, I also read that the 300's driveshaft is required, not sure if I can use the big reds differential or am stuck to the 300's, Alternatively, I skip all that and make a shock mount lift, not sure what 2" would give me for tire clearance though, have 12" rims, trying to go skinny and tall, 27 or bigger, any help or insight would be appreciated!
dougspcs
04-09-2016, 05:21 PM
What year is your 250?
The 85 has a different swing arm to the 86/87 due to changes with the rear diff and rear brake setup.
This will definitely affect the direct swap question.
If it's 85 none of it will fit the TRX300 swingarm..if it's 86/87 some might.
TRE8815
04-09-2016, 08:14 PM
I got the 86
dougspcs
04-10-2016, 04:53 PM
I had a look at my '90 TRX300 and it seems to be the same setup..
If it's a direct swap or not I couldn't say..you'd need to take some measurements of the front mount to start to see that the TRX swingarm will connect.
After that a bit of trial and error fab work..
But I'll ask, what are you looking to accomplish? Make it a better hill climber?
If so I'll tell you from personal experience, I've set mine up with better tires and can climb some pretty steep hills.
Unless you are doing something about the fact the 250ES is still just a 250, I'd save your time and effort.
I've climbed hills that robbed every ounce of torque from that motor..extending the swingarm wouldn't have helped me climb any better. She just plain ran out of power..
TRE8815
04-14-2016, 03:40 PM
I got a 350es kit, ported head, bigger valves, running a 300ex carb, I'm gonna be running some Interco interforce 2's, an extra 2 inches will help clearance, it's do able, I've found everything I would need on eBay for 250$ including bearings and seals, gotta check around to see what they did to extend the brake lines,
Powered by vBulletin® Version 4.2.2 Copyright © 2025 vBulletin Solutions, Inc. All rights reserved.