Something Failed, let’s find it! Transmission Analysis.

I am not rushing assembly, it’s not the place to rush or cut corners so this will take me a bit.

Everything shifts and spins as smoothly as would be expected with not being fully oiled yet, better than before that’s for sure.

Progress is made:
17760883-64BD-4861-9C6E-5EB8753FA3EF.jpeg
E72B35AA-6BE1-4B8E-8CD3-C1AAB7E779F4.jpeg
2381B0E9-1A11-47A3-924D-1D1392B29DB2.jpeg


New Circlips:
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PS: I hate you Triumph for your open ended detent spring lol. Would it have been THAT hard to leave another 90 degrees of wrap on the hook part?!
 
Substitute bolts found to fasten cases for a lot cheaper.

Triumph charges $7.67 per bolt for a M8x1.25 35mm Bolt used to hold the case halves together, you need 14. They’re single use...

I was going to order some probolt replacements, it those are $5.80 even.

Instead I found ARP exact replacements, 5 bolts for $16, definitely not single use lol. Bonus: They’re Black.

ARP 661-1004: Black Oxide, M8 x 1.25, 35mm UHL, Hex | JEGS
 
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Well trans is in the mail on the way back, throttle bodies are in the mail on the way out :)

I picked up a dremel, put on a sanding wheel, spun it up then realized “This not the right way”, so my TBs got packed up and are going out for a full taper bore to remove the internal lip, permanently remove the secondary haft, and increase total diameter since I am at the point where they’re now the next bottleneck.

Before pics:
26D27B7F-B3A8-4963-989A-3C3C1E7ECE52.jpeg 51DCCBD0-A05E-43F6-904D-1112A4CBD8F8.jpeg 178B1DDB-57EC-4D49-9BD6-7AD3D460C480.jpeg AB896D25-3646-4915-A41B-2948B1C38C21.jpeg 97ED7233-EC70-4578-A3AF-88A7F03C740E.jpeg 79387829-0443-45E2-A4F1-098F8F5C06E1.jpeg 5C6CCC20-3A95-4A62-8617-0B6E2132F202.jpeg F6795B48-8B1C-400A-8A9B-1CDB9DAB8FF9.jpeg AB06BA49-15D3-4351-AC83-A8A6688E9D11.jpeg

After Pics:
(Reserved)

In prep to send these out, I realized filling the left over secondary shaft holes is a lot better now, prior to having them bored out, so...

JB weld to the rescue! Thankfully the holes have a lateral face to secure the epoxy instead of it just being a plug, it’s shaped like a mushroom in cross section:
359CC68C-290C-4763-9E64-7CA14C5BC422.jpeg 5F516AC0-8609-413D-BB2C-485190342D9D.jpeg

Now about the secondary shaft, stepper, and sensor. A little time with a Dremel, some flat stock, and a drill will fix that up so I don’t catch engine codes from it.
3193FC58-BDE5-4527-97BE-CD0E7302187F.jpeg
 
Wet flow vs dry flow.

Wet flow, well, go back about 30 pages for some discussion.

Dry flow - the smoother the walls the better.

Turbulent in chamber = good!
Turbulent in runner = bad... up to a point, you want some.

These mods won’t change that in the slightest, but should (will?), increase both velocity and peak volume at peak HP.

But this isn’t about the finish, it’s about the lip. You can feel a not insignificant lip as a result of triumphs machining process where they go from a taper to a cylindrical bore down the TB about 1CM above the blades.

The math I did a few months ago resulted in a 56mm TB being a little bit undersized for my motor. Our TBs are 52mm at their outlet to the coupler, do definitely undersized for Steel and I, but oversized for stock cam motors. This is why Bob removes the secondaries, because the 265 kit is pushing the limits of the stock TBs.

I know at least one reader is cringing after a discussion we had, but, I’m going to be hard headed and stick to my intuition on this. I appreciate your advice and knowledge, I want to see for myself.

If I lose power, that’s fine, the forced induction guys will most definitely gain from doing what I’m doing, and I’m sure there’s a SC bike owner or two out there that wants free bolt on power in an even trade if this doesn’t work on an NA bike.



I’ll see nothing but gains from 2000-8000 RPM
.

Hopefully the engine is not running ****ty at idle because of lack of airspeedflow…
Don't the bottleneck - the stock diameters of the throttleblades- still will be the bottleneck =restriction airflow anyway, especially for a NA engine? Because,and we are talking about boostvolume/pressure=hp,not NA engines,
will boostvolume at (full) throttle not be the same, despite of machining the TB's ?

Do you also fixing the boost leakage of the primary throttle shaftbore ?
 
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In prep to send these out, I realized filling the left over secondary shaft holes is a lot better now, prior to having them bored out, so...

JB weld to the rescue! Thankfully the holes have a lateral face to secure the epoxy instead of it just being a plug, it’s shaped like a mushroom in cross section:
359CC68C-290C-4763-9E64-7CA14C5BC422.jpeg 5F516AC0-8609-413D-BB2C-485190342D9D.jpeg

Now about the secondary shaft, stepper, and sensor. A little time with a Dremel, some flat stock, and a drill will fix that up so I don’t catch engine codes from it.
3193FC58-BDE5-4527-97BE-CD0E7302187F.jpeg
Quick question what do you do with the secondary tps and motor once the shaft is gone.
 
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