The Honda PCX / Forza / ADV150 / SH Forums

I had to replace my throttlebody due to a bad IAC sensor going back and it not being sold separately.

Being im going to have a spare TB, I was thinking of porting and polishing the Bell (Opening of TB) as well as maybe opening up the Manifold as well. I plan to document and share the process.

Curious if anyone has done this? Hoping to have better throttle response. Im a sucker for snappy Throttles.

I'm curious to see what effects if any you might see. The opening of the throttle body and intake manifold has changed over the years.
I believe that Honda has made those openings narrower to increase air speed for better low end power. So depending if you only polish, or you do opening and polish, will get different results. That's just a guess. It should be a good project for theses Corona virus times.

I have a decent amount of experience porting and polishing. I did a lot of R&D on P&P carbs on our Rucks with amazing results so Im thinking if we clean up all casting marks and smooth everything else it might help a bit.

You definitely know what you are doing. What's your goal, more top end power?

Gil wrote:You definitely know what you are doing. What's your goal, more top end power?

No more top end. Im already hitting 77 on the limiter. I want snappier throttle. Im a sucker for snappy throttle response and maybe a little more midrange. Its kind of a dog between 30-60mph.

Got the new TB in the mail yesterday. So the new Throttle Body came with an entire wire harness. ha ha ha. Must have done some revisions. Pictures coming soon.

Started the Tear down on the Stock TB. Im keeping the new TB together and hacking the older one to experiment.
I wanted to pull out the shaft to see if there is enough meat on the shaft to single side it and trim down the Bolts. Unfortunately There are 2 seals that I dont see how to remove the shaft without destroying them.
At this point the only thing I can see where we can make improvements is the Manifold. Also if im not not mistaken being that this is Fuel Injected, you can Polish everything up to the Injector. No need for the rough texture on the runners to help with fuel atomization like you do in a carburated engine.

What I ended up doing is Wet sanding the casting marks on the Manifold. The Manifold doesnt have much meat on it to port as well as the TB.

Took some 600grit wet sanding paper and smoothed the whole thing. The Throttle response is a little noticable but the Smoothness of acceleration from 25-50 is really nice. Just keeps pushing. Also, the DAMN bike finally idling again with no issues. lol

Nice Work, I have a spare engine, I might just follow your lead.

Gil wrote:Nice Work, I have a spare engine, I might just follow your lead.

This is an easy mod you can do just to smooth the runner. I think bigger gains are to be made in the cylinder head. Might look into purchasing a new/used head and port and polish it.

New Cylinder head is $100+ so need to think about it first.