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It’s actually much much quicker and easier as well as really more precise to tune the fuel injection then carburetors ever were.

Especially with the auto tune box, I just give it a target table of air fuel on the chart and it takes care of everything automatically for me


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Ok- some more interesting stuff to report today.

As mentioned before, I noticed that the stacks on the 36mm Tb sit on the upper lip and although our 32mm Tb have the same lip- our stock stacks go all the way down the throat of the Tb and effectively make them 26mm.


So I decided to cut off the long portion, bore out the center similar to what I had done before- but also cut them short at the same height as the lip and then heat them up and shove a socket inside to stretch it wider to mate with the lip.


Cut-

[Image: d084df24f4240c4b4e0a6d17e194243f.jpg]




Bored-


[Image: 9913813ad747ca367444fdc79fc79496.jpg]



Hard to tell in pictures, but here are more-

[Image: 51d1df745b6052cc607d0bf852b9b1c4.jpg]

[Image: 36580b64d6e243176ee0921ec7f45a3b.jpg]

[Image: 8867797a40d9387234d4e79203c16438.jpg]

Compared to-

[Image: e1c5dab29ed7430a85fbd28c148f35a6.jpg]

[Image: 62ccb873bf52e1993710bf2d72f504c8.jpg]



So this took quite a bit of time as I needed to measure for it to sit right on the lip correctly. Although they would probably work quite well, I was still thinking there is room for improvement.

Since Honda uses very similar throttlebody design on most of its modern bikes, I started searching to see if they used 32 mm on any other bikes and then once I found those bikes I looked at their intake horn design.

Sure enough I found factory parts to fit the same 32 mm throttlebody housing and actually sit on the inside lip instead of choking off all the way down the bore to 26mm

It is my belief these will work better than the bored out stockers, and even my shortened and stretched stockers that I have not tested yet.

In fact due to the plug-and-play nature of these and the cheap cost I would think they now make the TSR pieces obsolete.

Stock on the left, new ones on the right.

[Image: 037ce53c5309c2b483118d9c4c9e37a3.jpg]


So I will be installing these which will drop right in, and then re-dyno in the spring.

Based on whatever results seen then, I will decide if I will move forward with fitting the 36 mm throttle bodies.


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No. 919 has 36mm TB.

I have a set of the 919 stacks though to go with my cb1000r 36mm Tb.

The 32mm stacks on the right are from a CB650R


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Thanks for the info PD,people have been -tinkering- for more power from day one. I'm doing cosmetic changes over the winter but at some point I'll be looking for more power and your digging for power here is greatly appreciated.
PD forgive my perhaps naive query, but in my head more horsepower equals more heat, so I'm wondering if you are looking into that?

'14 CB1100 STD 5 speed
(12-27-2020, 09:20 PM)tod.branko_imp Wrote: [ -> ]PD forgive my perhaps naive query, but in my head more horsepower equals more heat, so I'm wondering if you are looking into that?

'14 CB1100 STD 5 speed

More heat is the easiest part for to solve.
(12-27-2020, 10:02 PM)FLYTYM_imp Wrote: [ -> ]
(12-27-2020, 09:20 PM)tod.branko_imp Wrote: [ -> ]PD forgive my perhaps naive query, but in my head more horsepower equals more heat, so I'm wondering if you are looking into that?

'14 CB1100 STD 5 speed

More heat is the easiest part for to solve.

More heat is the easiest part for to solve.
Add water-jackets? Undecided

Add block fans? Sad

Go faster? Big Grin
Taking out the cat, and adding fuel both lower temps.


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(12-27-2020, 10:58 AM)PowerDubs_imp Wrote: [ -> ]No. 919 has 36mm TB.

I have a set of the 919 stacks though to go with my cb1000r 36mm Tb.

The 32mm stacks on the right are from a CB650R


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Dear PowerDubs,

I have to disassemble the airbox to replace the IACV.
Could it be a good idea to replace the stock stacks (26mm) with those of the CB650R (with hole 32mm)?
Are they plug and play?
Consider that my bike is completely stock.

Thanks for your reply
No- I would say wait- and see what results I get soon with my dual stacked custom made stacks.

They should give better results- but are NOT for a stock bike.

At the very least- you will need to add more fuel.

But also- there are many other ways to uncork the bike first- exhaust being the main one- get at least a slip on muffler, if not a full exhaust to get rid of the cat.

But no matter what- ANY change to the factory velocity stacks- you should add fuel.
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