YZ250 two-stroke carbon fiber engine mounts - with pics

Edited Date/Time 8/16/2018 7:07pm
G'day! I made a set of these for my last YZ, had them in the bike for two years and never encountered any issues (honestly, I could probably run no upper engine mounts and it wouldn't even matter). Thought I'd show some pics.

First I wet-laid some carbon weave with the resin, alternating the weave between each layer. This sandwiching of carbon has 13 layers, and had squished down to 3.5mm thick in my homemade aluminium block press. This was done a few weeks ago.

Traced out my original engine mounts onto the carbon weave, and cut them out. Happy with how they turned out, but now I need some prettier bolts!






*dons flame suit*
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6/21/2018 5:47pm
Your links don't work. Edit and delete the part ?format=750w and resubmit like below. Nice work though on the carbon. Maybe Team Green will chime in on this personal subject matter
6/21/2018 5:58pm
Your links don't work. Edit and delete the part [b]?format=750w[/b] and resubmit like below. Nice work though on the carbon. Maybe Team Green will chime in...
Your links don't work. Edit and delete the part ?format=750w and resubmit like below. Nice work though on the carbon. Maybe Team Green will chime in on this personal subject matter
Haha cheers for that man, all sorted now!

Yeah I'm pretty stoked on how these ones turned out. I made a set for my YZ125 a while ago, they were offset so it was it was a fair bit more effort.
Zesiger 112
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6/21/2018 6:14pm
How about pipe hangers? I've looked at getting a sheet of carbon and cutting and drilling out one like the factory bikes had.
make1go
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6/21/2018 6:54pm
if you dont know what the upper engine mounts do then i think you need to bone up. not a good sign

as for the mounts' they'd need a solid metal insert for the holes imo.

i stand be corrected by manny (team green) as he appears to be the most involved in cf that ive seen on this board.
1

The Shop

6/21/2018 7:28pm
make1go wrote:
if you dont know what the upper engine mounts do then i think you need to bone up. not a good sign as for the mounts'...
if you dont know what the upper engine mounts do then i think you need to bone up. not a good sign

as for the mounts' they'd need a solid metal insert for the holes imo.

i stand be corrected by manny (team green) as he appears to be the most involved in cf that ive seen on this board.
Dude, of course I know what the upper engine mounts do. It was a tongue-in-cheek comment. Relax.

The alternating weave pattern in the layers gives it plenty of bracing. As mentioned, I had a set in my old bike for two years of hard abuse, not a problem.
6/21/2018 7:40pm
How about pipe hangers? I've looked at getting a sheet of carbon and cutting and drilling out one like the factory bikes had.
I've actually got a homemade carbon pipe hanger on my bike now, I'll have to take a pic this weekend and post it! Turned out pretty ace. The carbon pipe hanger has actually been fitted to my last three YZs, still rocking.
dean122
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Upland, CA US
6/21/2018 7:41pm
Diamonds in the rough! Yikes, looks like the spark plug is petrified into the cylinder head.
6/21/2018 7:55pm
dean122 wrote:
Diamonds in the rough! Yikes, looks like the spark plug is petrified into the cylinder head.
Haha it's just a bit of mud. This bike gets used quite a lot Smile
newmann
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6/21/2018 9:07pm Edited Date/Time 6/21/2018 9:08pm
make1go wrote:
if you dont know what the upper engine mounts do then i think you need to bone up. not a good sign as for the mounts'...
if you dont know what the upper engine mounts do then i think you need to bone up. not a good sign

as for the mounts' they'd need a solid metal insert for the holes imo.

i stand be corrected by manny (team green) as he appears to be the most involved in cf that ive seen on this board.
DSP mounts from the early 2000's had no inserts.
ledger
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TN US
6/21/2018 9:28pm
You did a helluva nice job...Taking any orders ?
JBernard_401
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Boulder, CO US
6/21/2018 9:50pm
Im all for DIY. But if you are going to do any more. Way easier to get some CF plate, waterjet the profile, then sandwich it in some material and drill the holes with a bit made for CF.
6/22/2018 3:25am
Nice work!

I would look into getting some collars like the ones used for plastics so the bolts don’t wear the holes bigger or crack through.

Also, please clean your bike haha
2
Tiki
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6/22/2018 3:37pm
Out of curiosity, Why? I get the trick factor and the lightness. But did you notice any vibration dampening? Did you try changing the angle of the cylinder in the bike cradle? As far as trick, very cool. I commend your efforts to the cause.

Personally interested in any vibration dampening.
8/15/2018 5:28pm
How did head stays hold up being cf? I keep cracking head stay, was thinking about making a set out of carbon fiber.
lumpy790
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York, SC US
8/16/2018 7:07pm
Was talking to a CF manufacturer about making and distributing some some CF motor mounts and they said that the motor mount bolts will crush the CF so they make them with a metal insert so it can not crush it. Then then said to make the new model run for us we had to make a minimum of 50 sets so that kind of blew it out of the water.
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