I Finally Broke It [RXB250L]

zero_dgz · 08-17-2022, 02:44 PM

It took a while but I finally managed to develop a failure on my RXB250L. I don't think this is a specific knock against this bike; it could have happened to anyone.

I took it out on some real paint-shaker rocky trails surrounding the MABDR in Bald Eagle State Forest the day before yesterday, loaded up with luggage and camping gear, and managed to vibrate out both of the muffler mounting bolts. It turns out the little hanger tab at the midpipe could not, in fact, hold the entire muffler on for very long by itself. So it fell off, destroyed the graphite gasket at the midpipe junction, and melted my rear brake line and one of the little plastic clips that holds the brake line to the swingarm because as you'd imagine the entire exhaust pipe is bloody hot. Loctite did not do the job in this case... I suspect enough heat is generated in that area to make blue Loctite let go.

https://imgur.com/ebrtKDk

Womp womp.

Luckily the bolt that goes on the hanger tab is the same size as the original mounting bolts for the muffler -- and I still had that, so I used it to hang the muffler long enough to carefully get out of there... with no rear brakes...

The guys at Track N Trail powersports in Spring Mills, PA were very helpful and got me some extra bolts (for free, no less) to jigger my exhaust back together as best as was possible but they did not have a brake line lying around. So I rode home 175+ miles taking all back roads with no rear brake. Some of those big downhills were pretty sketchy, but I did not die and here I am to tell the tale.

For anyone that needs this info in the future, the rear brake line on the RXB appears to be 60cm, with a 90 degree elbow on the caliper end and the typical 22 degree one on the master cylinder end. Available online for $9 from the usual scumbags. From the factory it goes forward a small distance with a U bend in it, presumably to accommodate the suspension travel of the swingarm, then back to the caliper. If you decided to eliminate the U bend you could probably make do with a shorter line. I still have the exhaust hanger tab as well, so I'll line everything up and weld that back on later. I did not remember to measure the diameters for the graphite gasket in the midpipe junction before leaving this morning, but I'll do that later and post it as well. I will likely also design and 3D print a replacement for the little brake line retainer dingus that I also melted, which is just held in with a single screw, and post the file for that when I have it done. (You could also just take a flat strip of metal, bend it 270 degrees around about a 3/8" mandrel, and drill a hole in it and that'd work just as well.)

As a consolation prize, here is my RXB's mirror overlooking a vista: https://imgur.com/NLwayqY

tknj99 · 08-17-2022, 03:24 PM

Don't feel so bad.. i've had my rear wheel fall off while riding.. made for not so much of a good day.. ended up drilling the axles and adding cotter pins to be extra safe. This is on a Titan DLX which is very similar to the old RXB 250 with 229cc engine

Wild Dog · 08-18-2022, 03:33 PM

For those hot areas, it's ideal to use loctite 266. It's rated for high temp, for the rest i loctite 242 is a good choice.

kevperro · 08-18-2022, 11:35 PM

My cousin almost killed himself in the 1970s on a Honda CT90. I think he spent like 6-months in the hospital because of a wheel that came off.

You really have to keep on top of bike maintenance. There is nothing magical about brands.

08-17-2022, 02:44 PM	#1
zero_dgz Join Date: Jan 2020 Posts: 258	I Finally Broke It [RXB250L] It took a while but I finally managed to develop a failure on my RXB250L. I don't think this is a specific knock against this bike; it could have happened to anyone. I took it out on some real paint-shaker rocky trails surrounding the MABDR in Bald Eagle State Forest the day before yesterday, loaded up with luggage and camping gear, and managed to vibrate out both of the muffler mounting bolts. It turns out the little hanger tab at the midpipe could not, in fact, hold the entire muffler on for very long by itself. So it fell off, destroyed the graphite gasket at the midpipe junction, and melted my rear brake line and one of the little plastic clips that holds the brake line to the swingarm because as you'd imagine the entire exhaust pipe is bloody hot. Loctite did not do the job in this case... I suspect enough heat is generated in that area to make blue Loctite let go. https://imgur.com/ebrtKDk Womp womp. Luckily the bolt that goes on the hanger tab is the same size as the original mounting bolts for the muffler -- and I still had that, so I used it to hang the muffler long enough to carefully get out of there... with no rear brakes... The guys at Track N Trail powersports in Spring Mills, PA were very helpful and got me some extra bolts (for free, no less) to jigger my exhaust back together as best as was possible but they did not have a brake line lying around. So I rode home 175+ miles taking all back roads with no rear brake. Some of those big downhills were pretty sketchy, but I did not die and here I am to tell the tale. For anyone that needs this info in the future, the rear brake line on the RXB appears to be 60cm, with a 90 degree elbow on the caliper end and the typical 22 degree one on the master cylinder end. Available online for $9 from the usual scumbags. From the factory it goes forward a small distance with a U bend in it, presumably to accommodate the suspension travel of the swingarm, then back to the caliper. If you decided to eliminate the U bend you could probably make do with a shorter line. I still have the exhaust hanger tab as well, so I'll line everything up and weld that back on later. I did not remember to measure the diameters for the graphite gasket in the midpipe junction before leaving this morning, but I'll do that later and post it as well. I will likely also design and 3D print a replacement for the little brake line retainer dingus that I also melted, which is just held in with a single screw, and post the file for that when I have it done. (You could also just take a flat strip of metal, bend it 270 degrees around about a 3/8" mandrel, and drill a hole in it and that'd work just as well.) As a consolation prize, here is my RXB's mirror overlooking a vista: https://imgur.com/NLwayqY
	1

08-17-2022, 03:24 PM	#2
tknj99 Join Date: Oct 2020 Location: Central VA Posts: 1,259	Don't feel so bad.. i've had my rear wheel fall off while riding.. made for not so much of a good day.. ended up drilling the axles and adding cotter pins to be extra safe. This is on a Titan DLX which is very similar to the old RXB 250 with 229cc engine __________________ 2024 Zuma Storm 150 DLX 2019 Beta 430 RRS 2018 VStrom 1000 XT Former China Bikes: Tao DBX1, Brozz 250, CSC RX4, Titan DLX, Templar X
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08-18-2022, 11:35 PM	#4
kevperro Join Date: May 2022 Location: Washington Posts: 25	Bolts My cousin almost killed himself in the 1970s on a Honda CT90. I think he spent like 6-months in the hospital because of a wheel that came off. You really have to keep on top of bike maintenance. There is nothing magical about brands.
	1

08-18-2022, 03:33 PM	#3
Wild Dog Join Date: Dec 2016 Location: Argentina Posts: 756	For those hot areas, it's ideal to use loctite 266. It's rated for high temp, for the rest i loctite 242 is a good choice.
	0