Yamaha sidewinder srx 2019 top end problem

Qcriders

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Québec
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Yamaha sidewinder srx 2019
Yamaha srx440 1980
2x Yamaha enticer 300 1980
Hi everyone.
My srx has no top end whatsoever.
Here’s the setup I’m running:
Tune: stage 3 multimap pefi (with the 2.5inch pefi exhaust)
Clutching;
Primary:
green dalton spring
Dalton dtay1 ramps set to 75.5g
Secondary:
Dalton orange spring
41/37 helix
Preload set to 1-6
Track: 2 inch lugs no studs.

My problem:
Instead of reaching 9000rpm like the tune says I should, i only reach 7800rpm - 110kmh.
When I’m wide open, the knock light appears once I reach my plateau and disappears when I let off the throttle. (I run 91 octane with octane booster and still didn’t fix)
I need help.
 
You should monitor boost. I’d be suspicious on a leak. Stock BOV?
 
You should monitor boost. I’d be suspicious on a leak. Stock BOV?
No boost leak all the test related to that have been performed. In a pull I’m building 20psi
Stock bov
 


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