TZR125 4DL
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Reedblock changing

TZR125 Track Bike
Managed to make two reedblocks for testing
Reedblock 1) is a creation from myself.
Reedblock 2) is changed to Martin77 dimensions
These mod's are done because the stock reedblock ar very small, these modifications in combination with the 32mm carb should at least help the engine.
What they do, that's the question and will be tested on the dyno
What a hobby we have, in the snow to the workshop
My modification is just cutting the two bridges
Its easy to do, it wont take long
After smoothing, it is giving a nice open window.
Opened the end a bid, and rounded it off
Smoothing the inlet with a bid off sandpaper
Matin77 design is more specific, they also need the bridges

Smoothing it to certain rounding's, curves and dimensions

It gives more attention to the flow.
Also the bridges are to support the reed's them self in order not to break
As comparison next to each other
The complete open window should theoretical give more, but how long the reeds are holding that is the question
I would say both are interesting to test
Here with 0,35mm carbon reeds
Looking good
Bending the big petal
After measuring the results, I was a little bid disappointed.
You can see the changing's helped in the mid section (gained about 1HP roughly) but on peek power the results where the same.
Even the change between the removed bridge and flowed reedblock was limited (no difference at peek power)
So started to work out where the problem lies
My findings are:
surface Reedblock.
Petal wide open 11mm
Wide window 12,8mm
11X12,8=140,8mm2
6X140,8=844,8mm2
Reedblock=844,8mm2

Surface carb (32mm)
16X16X3,14=803.84mm2
Carb=803,84mm2

Surface carb (34mm)
17X17X3.14=907.46mm2

So theoretical the reedblock should be big enough for the 32mm carb.
For a 34mm you should enlarge the windows (witch is doable)
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