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2020 Honda Monkey and others
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Discussion Starter #1
Just got my kit after waiting for forever it seems. Intake port looks beautiful and is matched to the intake manifold.

The exhaust port is tiny! Like not even touched tiny.

Also, I thought these heads had the O2 port filled in? I could run a stock O2 sensor just like factory and cut off flow, just like factory does.

89368


Intake is much better.

89369
 

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Discussion Starter #2
Went to a machine shop to see what they would charge to open the exhaust port and after some hemming and hawing the guy said $255.

No way I'm paying that for a little playing around with a grinder bit. He was cool and said go to Harbor Freight and get a cheap grinder and a few bits and take some material out. Save a bunch of money and time since they are busy.

That is what I will be doing.
 

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You can send it to me and I can do a street port I usually charge 100 but I can work something out
 
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Discussion Starter #4
You can send it to me and I can do a street port I usually charge 100 but I can work something out
I'm going to get a die grinder and some bits and open it up to match the exhaust gasket and smooth it into the existing port.

If I'm really feeling frisky I'll get some polishing bits as well to make a mirror finish in there since it is a rough cast.

Still cannot believe how they hogged out and beautifully finished the intake side and left the exhaust side tiny.
 

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Get a plug for the sensor hole. Thats what I did to mine.

Also, be very careful not to damage valve seats when grinding your exhaust port. It needs to be a nice taper from the valves all the way to the port. Just grinding back the port face won't give you much gains. The ring of soot in the picture is deceptive, but mine is enlarged from 21mm to 26mm on the exhaust side. Intake side is 33mm (up from 28mm standard or 30mm for the 5 axis)

89409

89411
 

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Discussion Starter #10
Get a plug for the sensor hole. Thats what I did to mine.

Also, be very careful not to damage valve seats when grinding your exhaust port. It needs to be a nice taper from the valves all the way to the port. Just grinding back the port face won't give you much gains. The ring of soot in the picture is deceptive, but mine is enlarged from 21mm to 26mm on the exhaust side. Intake side is 33mm (up from 28mm standard or 30mm for the 5 axis)

View attachment 89409
View attachment 89411
I just want the exit opened and smoothed into the port.

Do you have pics of the stock part before the darkness hit?
 

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Discussion Starter #12
Get a plug for the sensor hole. Thats what I did to mine.

Also, be very careful not to damage valve seats when grinding your exhaust port. It needs to be a nice taper from the valves all the way to the port. Just grinding back the port face won't give you much gains. The ring of soot in the picture is deceptive, but mine is enlarged from 21mm to 26mm on the exhaust side. Intake side is 33mm (up from 28mm standard or 30mm for the 5 axis)

View attachment 89409
View attachment 89411
I'm leaving my 5 axis machined intake side alone and I've dropped off the head with a pro to open up the exhaust.

I just want the opening to match the gasket and blend into the existing port.

Still undecided to take the bike to DynoJet to have them dyno tune it with the PV3 or bite the bullet and get the ARacer setup and dial it in myself.
 

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I'm leaving my 5 axis machined intake side alone and I've dropped off the head with a pro to open up the exhaust.

I just want the opening to match the gasket and blend into the existing port.

Still undecided to take the bike to DynoJet to have them dyno tune it with the PV3 or bite the bullet and get the ARacer setup and dial it in myself.
If you go down the aracer route, go a rc super 2. If you do the PV3, I can send you some more stuff to help
 

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Discussion Starter #14
If you go down the aracer route, go a rc super 2. If you do the PV3, I can send you some more stuff to help
Based on having the exhaust port opened up, 15/15d cam, running a low pipe which I'll remove baffles if there are any.

Would you recommend the 37mm throttle body and ARacer?

I'm not trying to make it rev to the moon but if the bike picks up big gains I'll add those to the build.

As for tuning with PV3, I'm sure Chris at DJ would like any available mapping if you have it. I don't think they have any Takegawa 4v maps which is why they wanted me to get it.
 

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Based on having the exhaust port opened up, 15/15d cam, running a low pipe which I'll remove baffles if there are any.

Would you recommend the 37mm throttle body and ARacer?

I'm not trying to make it rev to the moon but if the bike picks up big gains I'll add those to the build.

As for tuning with PV3, I'm sure Chris at DJ would like any available mapping if you have it. I don't think they have any Takegawa 4v maps which is why they wanted me to get it.
The 5 axis port is done to suit the 34mm throttle. A 37 won't get you any more unless you're opening up the intake port to suit. On standard ports, mine actually went worse with the 37. Now its off it head, but it has the porting and compression to suit the 37.

Your biggest downside to the pv3 is that the rev limit can only go up to 11.4k. If you wanna go higher, then buy an aracer.

I can send you/Chris my map, but keep in mind that my setup is different to yours (ported, reshaped chamber, DCR custom cam, 37mm throttle, forza injector (235ccm)) and my map is not directly compatible with your bike (Aus monkey and USA monkey use different .stk files). Chris will know what to do in terms of copying stuff over.
 

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Discussion Starter #16
The 5 axis port is done to suit the 34mm throttle. A 37 won't get you any more unless you're opening up the intake port to suit. On standard ports, mine actually went worse with the 37. Now its off it head, but it has the porting and compression to suit the 37.

Your biggest downside to the pv3 is that the rev limit can only go up to 11.4k. If you wanna go higher, then buy an aracer.

I can send you/Chris my map, but keep in mind that my setup is different to yours (ported, reshaped chamber, DCR custom cam, 37mm throttle, forza injector (235ccm)) and my map is not directly compatible with your bike (Aus monkey and USA monkey use different .stk files). Chris will know what to do in terms of copying stuff over.
Knowing what I'm using on mine would you recommend just going ARacer?
 

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Probably not. You'd be spending 1k to get maybe 500 more usable rpm. What's the point?

As long as you're willing to learn the pv3 or let someone in the know tune it, it's a good unit.

Sent from my Atom_XL using Tapatalk
 

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Discussion Starter #18
Probably not. You'd be spending 1k to get maybe 500 more usable rpm. What's the point?

As long as you're willing to learn the pv3 or let someone in the know tune it, it's a good unit.

Sent from my Atom_XL using Tapatalk
I just want the most performance possible from my setup. If it were worth 2+ hp I'd switch over.

@Ghostrider.1127 seems to prefer ARacer over PV3 and he has a similar build.
 

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I just want the most performance possible from my setup. If it were worth 2+ hp I'd switch over.

@Ghostrider.1127 seems to prefer ARacer over PV3 and he has a similar build.
The aracer is more straightforward to setup. As an example, there's 3 tables that need to be changed if you want to modify the spark timing in the PV3. If you only change one, then you'll find that the datalogged spark timing will be under what you want or sometimes use stock timing and sometimes use modified timing. It's quirks like that which ruin the PV3's reputation and stops people from getting the performance that they want from it.

Since you already own the pv3, may as well learn the ins and outs and save some cash
 
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