Tom Morgan YZ315 Stroker (Red Bull Straight Rhythm)

Zesiger 112
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Zesiger 112 7/21/2019 4:00pm
7/21/2019 4:00pm
Yz229 wrote:
I want to do swing arm, maybe some Ti, big brakes... Already have the 2008 CRF Master cylinder and stock 270mm rotor. Would like to do...
I want to do swing arm, maybe some Ti, big brakes...

Already have the 2008 CRF Master cylinder and stock 270mm rotor. Would like to do the Motostuff caliper and 280mm rotor but that's almost a grand!

What Ti bolt kit did you get?
Zesiger 112 wrote:
270 is plenty. I bought my stuff from docwob on eBay. They have specialty kit stuff like kick starter bolt, small screws, master cylinder bolts. But...
270 is plenty. I bought my stuff from docwob on eBay. They have specialty kit stuff like kick starter bolt, small screws, master cylinder bolts. But for just normal bolts motostuff is pretty reasonable price you just have to take time and measure and list your sizes. And if you buy something from them for the first time they send a discount code for next purchase. I used that for Ti
Yz229 wrote:
I found his eBay store, will check it out! Thanks!
One thing, all their items are listed separately and therefore they charge individual shipping, so when you pay in the cart it will be crazy expensive. Just send them a message and they will reimburse the shipping charges on a multi item order.
Yz229
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Yz229 7/24/2019 3:51pm
7/24/2019 3:51pm Edited Date/Time 7/24/2019 4:06pm
Billy got it it squared away! I think it was .100"offset but Billy measured, lathed it and installed a spacer. Will be cleaning it all up and re-greasing everything!




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Luxon MX
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Luxon MX 7/24/2019 4:35pm
7/24/2019 4:35pm
It went pretty smoothly, we bolted it all up and measured the offset. It's kind of hard to get a good measurement since everything can float around so much, but I came up with .100" (2.5mm) and started with that. There's actually enough float in the system that you could bolt it all up as-is and it would probably work, but everything was biased to one side and that's certainly not ideal. So I took off .100" from the swingarm and made a spacer to account for that for the other side. We bolted that up and everything was pretty much centered, so we called it good.





It sure looks a lot nicer now with the more modern swingarm, not sure why Yamaha doesn't just go this route and consolidate some part numbers. Maybe they have a huge inventory of two-stroke swingarms laying around?
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Yz229
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Yz229 7/25/2019 1:22pm
7/25/2019 1:22pm
Next item on the agenda. Ride Engineering vs Motostuff front calipers? Ride Engineering is much cheaper, especially on RMATV!

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cdoggy81
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cdoggy81 7/25/2019 1:41pm
7/25/2019 1:41pm
See, I knew you were in good hands with Billy Smile & going off memory plus all the play in the linkage I was “pretty close” on the measurement... LoL 😂
Nice work guys!
Yz229
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Yz229 7/25/2019 4:55pm
7/25/2019 4:55pm
Yep for sure! Was pretty easy for him.

I want to bring bike to Red Bull Straight Rhythm. Who wants to ride it? Smile
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Luxon MX
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Luxon MX 7/26/2019 12:43pm
7/26/2019 12:43pm
Yz229 wrote:
Next item on the agenda. Ride Engineering vs Motostuff front calipers? Ride Engineering is much cheaper, especially on RMATV!
Honda master cylinder and caliper, plus an oversized rotor is much cheaper and works great. But not as blingy...


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Luxon MX 7/26/2019 12:44pm
7/26/2019 12:44pm
cdoggy81 wrote:
See, I knew you were in good hands with Billy :) & going off memory plus all the play in the linkage I was “pretty close”...
See, I knew you were in good hands with Billy Smile & going off memory plus all the play in the linkage I was “pretty close” on the measurement... LoL 😂
Nice work guys!
There's enough float in the linkage that you could probably be anywhere between .100 and .175 and it would work just fine really.
Yz229
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Yz229 7/26/2019 12:51pm
7/26/2019 12:51pm
Yz229 wrote:
Next item on the agenda. Ride Engineering vs Motostuff front calipers? Ride Engineering is much cheaper, especially on RMATV!
Luxon MX wrote:
Honda master cylinder and caliper, plus an oversized rotor is much cheaper and works great. But not as blingy...


That's actually what it has right now, 2008 CRF450 MC, Caliper, steel braided line, new Honda pads and stock Yamaha 270mm floating disc.

If the after market calipers aren't much different, I'll just skip it.
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Luxon MX 7/26/2019 1:20pm
7/26/2019 1:20pm
Yz229 wrote:
That's actually what it has right now, 2008 CRF450 MC, Caliper, steel braided line, new Honda pads and stock Yamaha 270mm floating disc. If the after...
That's actually what it has right now, 2008 CRF450 MC, Caliper, steel braided line, new Honda pads and stock Yamaha 270mm floating disc.

If the after market calipers aren't much different, I'll just skip it.
Only things they can change in a caliper are the piston sizes and the stiffness (stiffer is better). I'm not sure whether they change the pistons or not, but just from looking at it, they don't look a whole lot stiffer than stock. I'd just upgrade to a 280mm rotor and be done with it!
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Zesiger 112
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Zesiger 112 7/29/2019 5:43am
7/29/2019 5:43am
Hey I have a discount code for motostuff. Send me a message and I'll let you try it.
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PJSMAN 7/29/2019 5:49am
7/29/2019 5:49am
Yz229 wrote:
Talking to Billy @ Luxon about this. Will be bringing bike up there to figure it out!

Thanks guys!
What jetting did you end up with ....since the carb is taper bored? thanks
Yz229
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Yz229 7/29/2019 7:52am
7/29/2019 7:52am
Zesiger 112 wrote:
Hey I have a discount code for motostuff. Send me a message and I'll let you try it.
Yeah, I'll try! How long is it good for? I think Billy is right, my calipers are probably good enough. But little more leverage from 280mm rotor might be worth it.

Thanks
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Yz229 7/29/2019 7:55am
7/29/2019 7:55am Edited Date/Time 7/29/2019 7:59am
Yz229 wrote:
Talking to Billy @ Luxon about this. Will be bringing bike up there to figure it out!

Thanks guys!
PJSMAN wrote:
What jetting did you end up with ....since the carb is taper bored? thanks
Taper didn't change it much. I tried from 182-190 main.

188-190 is it's sputter point on top end. 185 clears up nicely, but I have 182 in now. May go back to 185 main.

Needle N3EW 2nd position

Pilot 55 about

Power Jet 55

Air screw .75 turns out

VP C12 with Redline 48:1
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PJSMAN 7/29/2019 8:01am
7/29/2019 8:01am
Yz229 wrote:
Talking to Billy @ Luxon about this. Will be bringing bike up there to figure it out!

Thanks guys!
PJSMAN wrote:
What jetting did you end up with ....since the carb is taper bored? thanks
Yz229 wrote:
Taper didn't change it much. I tried from 182-190 main. 188-190 is it's sputter point on top end. 185 clears up nicely, but I have 182...
Taper didn't change it much. I tried from 182-190 main.

188-190 is it's sputter point on top end. 185 clears up nicely, but I have 182 in now. May go back to 185 main.

Needle N3EW 2nd position

Pilot 55 about

Power Jet 55

Air screw .75 turns out

VP C12 with Redline 48:1
thanks
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PJSMAN 7/29/2019 8:09am
7/29/2019 8:09am
Yz229 wrote:
And it's all done for now! Tom got the top end to me and that was the last needed. Rode it up and down the street...
And it's all done for now! Tom got the top end to me and that was the last needed. Rode it up and down the street for now.





What size piston did it end up being and how much stroke was added to the crank? thanks
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Yz229 7/29/2019 8:15am
7/29/2019 8:15am
72mm bore x 76mm stroke.
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PJSMAN 7/29/2019 8:20am
7/29/2019 8:20am
Yz229 wrote:
72mm bore x 76mm stroke.
Nice.......with a 40mm taper bore on the carb?

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Yz229
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Yz229 7/29/2019 8:28am
7/29/2019 8:28am
It's effectively 41mm with combination of bore and hand porting of carb and reedblock.
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Zesiger 112
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Zesiger 112 7/29/2019 8:33am
7/29/2019 8:33am
Zesiger 112 wrote:
Hey I have a discount code for motostuff. Send me a message and I'll let you try it.
Yz229 wrote:
Yeah, I'll try! How long is it good for? I think Billy is right, my calipers are probably good enough. But little more leverage from 280mm...
Yeah, I'll try! How long is it good for? I think Billy is right, my calipers are probably good enough. But little more leverage from 280mm rotor might be worth it.

Thanks
Sent you the code through message. Good until the 31st
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cdoggy81 7/29/2019 10:13am
7/29/2019 10:13am
Would love to see some dyno numbers on that bad boy!!! You can only do so much with an overbore so that 4mm extra stoke is where these things really pick up power. Really looking fw to hearing how she rides 😎
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Yz229 7/29/2019 11:25am
7/29/2019 11:25am
I'm guessing 58HP... Maybe 60 on a happy Dyno. Stroking is where the power is at, but not cheap! One day I will ride it Smile
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PJSMAN 7/29/2019 11:30am
7/29/2019 11:30am
Yz229 wrote:
I'm guessing 58HP... Maybe 60 on a happy Dyno. Stroking is where the power is at, but not cheap! One day I will ride it Smile
Did Tom go with the YZ250X (5th Gear)? in the transmission
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Yz229 7/29/2019 11:33am
7/29/2019 11:33am
Well I asked him to since it was already apart
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cdoggy81 7/29/2019 12:35pm
7/29/2019 12:35pm
Yz229 wrote:
I'm guessing 58HP... Maybe 60 on a happy Dyno. Stroking is where the power is at, but not cheap! One day I will ride it Smile
Yep... the 3 main builders I talked to all said the same about stroking. It was at the moment I got the quotes I opted for just the overbore & porting... LoL
I would be super happy just to hit 50-51 with mine. With all your goodies 58-60 would be doable no prob. You’ll be smoking those 450’s fo sho! 💨 (pun intended)
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Yz229 7/29/2019 1:49pm
7/29/2019 1:49pm
Yz229 wrote:
I'm guessing 58HP... Maybe 60 on a happy Dyno. Stroking is where the power is at, but not cheap! One day I will ride it Smile
cdoggy81 wrote:
Yep... the 3 main builders I talked to all said the same about stroking. It was at the moment I got the quotes I opted for...
Yep... the 3 main builders I talked to all said the same about stroking. It was at the moment I got the quotes I opted for just the overbore & porting... LoL
I would be super happy just to hit 50-51 with mine. With all your goodies 58-60 would be doable no prob. You’ll be smoking those 450’s fo sho! 💨 (pun intended)
I forgot, whats he doing to yours? I know he said a ported YZ295 was 49HP on his dyno, but I think his reads a little low. New stock on his dyno was 44, but I know some other dynos get 46.

Not that important anyway, as long as on same dyno you get improvements with same bike!
Yz229
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Yz229 7/29/2019 1:51pm
7/29/2019 1:51pm
Just got proof for swing arm graphics. Had to put Luxon on since he helped me out with it!


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cdoggy81 7/29/2019 2:53pm
7/29/2019 2:53pm
265 with the high comp head (T2/Sunoco 110 mix). Said the head was worth 2hp on race gas over pump but maybe I added those 2 ponies in there twice... LoL 😂 I’ll probably be closer to 48 if stock was 44. I did add VF3R & a pipe so who knows. As long as I can stay closer to my 450 friends I’ll be happy 😁
Yz229
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Yz229 7/30/2019 12:39pm
7/30/2019 12:39pm Edited Date/Time 7/30/2019 2:40pm
Those with YZ450F swingarms, did you have to get a longer chainl? Mine is a bit too short now vs YZ250 swingarm.

I'm all the way forward and the chain is still too tight. Both the YZ250 and 2014 YZ450F OEM chain is 114 links.

Also, looks like I'm stuck with the 270mm rotor. The MotoStuff is for 2008+, and mounting is different on the lower forks. I made this mistake before!
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cdoggy81 7/30/2019 2:55pm
7/30/2019 2:55pm
Hmm... I’m running 114 as well but will verify when I get a chance. I’m also running a 14 / 51 gearing as well. What are you running? With all that horsepower you may want to consider a 49 to start...

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