Cold-blooded Hawk

manco15158 · 09-05-2020, 12:29 AM

Hello,

I bought a 2020 Hawk off Amazon a few months ago. I upgraded the exhaust and carb right away. I replaced the PZ30 with the Mikuni VM26 672U clone, which from what I've read on these forums, is a clone of the real Mikuni. In order to get the bike running (it has been warm here in Ohio), I have to put it on full choke and give it some throttle for a few seconds. Then, even after running on full choke for five minutes, it will still die a few seconds after putting it on half choke.

I immediately replaced the stock main jet with a 110. I've scoured the internet, including Youtube and forums, and have tried everything I could find. So far, I have installed every size of main jet from 110 to 130 into the Mikuni clone and have set the mixture screw from 2-3 turns out on each main jet. I also tried several sizes of main jet and mixture screw combinations on the PZ30 as well.

After getting frustrated, I took the bike to a mechanic, who upgraded the sprockets and chain for me. He told me that it's just super cold blooded. It runs and rides great when I can get it running, but I am not seeing where anyone else is having so many problems getting this thing started and warmed up. I would greatly appreciate any wisdom someone could offer me. Thanks!

TheChairman · 09-05-2020, 01:33 AM

What are you using for a pilot jet? Was that upgraded as well?

How is the valve adjustment?

Oddball Matt · 09-05-2020, 04:26 AM

Main jet only affects wide open throttle, as Thechairman suggested you should be focusing on the idle circuit a.k.a the pilot jet. And as also suggested do the valves, can't get it right if the valves are too tight

Bruces · 09-05-2020, 07:42 AM

Adjust the valves !

gwowzer · 09-05-2020, 09:08 AM

Yup, valves and change the pilot jet out. I was running a 38 in my brozz and it was doing well stock. Where you at in Ohio, btw? I'm near Newark

manco15158 · 09-05-2020, 09:08 AM

I’m using the stock pilot jet. And I will adjust the valves and then, try the pilot jet. Thanks!

manco15158 · 09-05-2020, 09:09 AM

Quote:

Originally Posted by gwowzer

Yup, valves and change the pilot jet out. I was running a 38 in my brozz and it was doing well stock. Where you at in Ohio, btw? I'm near Newark

Delta, OH

gwowzer · 09-05-2020, 09:15 AM

Ah, you are way up there lol. Always looking for riding buddies.
Do you have a set of pilot jets for that carb?

manco15158 · 09-05-2020, 09:39 AM

Quote:

Originally Posted by gwowzer

Ah, you are way up there lol. Always looking for riding buddies.
Do you have a set of pilot jets for that carb?

Lol, yes almost to Michigan. No I do not have a set of pilot carbs, so I’ll have to wait the many weeks for them to get shipped to my house thanks to all the slow shipping that’s been occurring lately. That has added to the nightmare of trying to fix anything.

manco15158 · 09-05-2020, 01:14 PM

Ok I adjusted the valves. It’s gonna be three weeks before the pilot jets get here. It starts and warms up fine with the choke. However, now, it bogs down when I ge to fifth gear and stalls out.

gwowzer · 09-05-2020, 02:04 PM

You are turning the choke back off before riding, right?
Do you have pictures of the pilot jets in your carb?

manco15158 · 09-05-2020, 03:25 PM

Quote:

Originally Posted by gwowzer

You are turning the choke back off before riding, right?
Do you have pictures of the pilot jets in your carb?

Yes, I am turning off the choke. I am able to get it warmed up with the valve change, now. It still requires the choke, but unlike before, I am able to turn it off once it’s warmed up. Gonna take it apart this evening and I will get a picture of it.

manco15158 · 09-05-2020, 05:02 PM

Ok, bumped the main jet up to a 135 and turned the mixture screw to 2 turns. This solved the issue in 5th gear. Have to use the choke to start it but it warms up to where no choke is needed. The valve adjustments definitely helped. I will change the pilot jet when it comes to hopefully fix the choke issue. I attached a photo of my pilot jet and carb. Thanks everyone for the help!

Baby Huey · 09-06-2020, 09:42 AM

Just a suggestion. Make sure that you don't have a vacuum leak on the intake manifold.

I think that I remember Motocheese finding that his carb didn't seal properly until he added some washers to the mounting bolts.

aaw611 · 09-08-2020, 12:33 AM

That main jet sounds wayyy huge. Any of the idle/choke issues are going to be related to the pilot jet. That's what you should be focusing on in my opinion.

09-05-2020, 12:29 AM	#1
manco15158 Join Date: Sep 2020 Location: Delta, OH Posts: 9	Cold-blooded Hawk Hello, I bought a 2020 Hawk off Amazon a few months ago. I upgraded the exhaust and carb right away. I replaced the PZ30 with the Mikuni VM26 672U clone, which from what I've read on these forums, is a clone of the real Mikuni. In order to get the bike running (it has been warm here in Ohio), I have to put it on full choke and give it some throttle for a few seconds. Then, even after running on full choke for five minutes, it will still die a few seconds after putting it on half choke. I immediately replaced the stock main jet with a 110. I've scoured the internet, including Youtube and forums, and have tried everything I could find. So far, I have installed every size of main jet from 110 to 130 into the Mikuni clone and have set the mixture screw from 2-3 turns out on each main jet. I also tried several sizes of main jet and mixture screw combinations on the PZ30 as well. After getting frustrated, I took the bike to a mechanic, who upgraded the sprockets and chain for me. He told me that it's just super cold blooded. It runs and rides great when I can get it running, but I am not seeing where anyone else is having so many problems getting this thing started and warmed up. I would greatly appreciate any wisdom someone could offer me. Thanks!
	0

09-05-2020, 04:26 AM	#3
Oddball Matt Join Date: Jan 2020 Location: Vääksy, Finland Posts: 401	Main jet only affects wide open throttle, as Thechairman suggested you should be focusing on the idle circuit a.k.a the pilot jet. And as also suggested do the valves, can't get it right if the valves are too tight __________________ 2004 Longjia Grido 50 scooter 1999 Cagiva Mito 125 Evo, Yamaha XV125 engine, Ducati SS fairings, getting turboed 1993 Yamaha GTS 1000 Ex:Bashan BS200-S7 `07 Streetfighter-quad
	0

09-05-2020, 01:33 AM	#2
TheChairman Join Date: May 2020 Location: Philadelphia Posts: 115	What are you using for a pilot jet? Was that upgraded as well? How is the valve adjustment?
	0

09-05-2020, 07:42 AM	#4
Bruces Join Date: May 2018 Posts: 1,584	Adjust the valves !
	0

09-05-2020, 09:08 AM	#5
gwowzer Join Date: Aug 2019 Location: Central Ohio Posts: 297	Yup, valves and change the pilot jet out. I was running a 38 in my brozz and it was doing well stock. Where you at in Ohio, btw? I'm near Newark
	0

09-05-2020, 09:15 AM	#8
gwowzer Join Date: Aug 2019 Location: Central Ohio Posts: 297	Ah, you are way up there lol. Always looking for riding buddies. Do you have a set of pilot jets for that carb?
	0

09-05-2020, 01:14 PM	#10
manco15158 Join Date: Sep 2020 Location: Delta, OH Posts: 9	Ok I adjusted the valves. It’s gonna be three weeks before the pilot jets get here. It starts and warms up fine with the choke. However, now, it bogs down when I ge to fifth gear and stalls out.
	0

09-05-2020, 02:04 PM	#11
gwowzer Join Date: Aug 2019 Location: Central Ohio Posts: 297	You are turning the choke back off before riding, right? Do you have pictures of the pilot jets in your carb?
	1

09-06-2020, 09:42 AM	#14
Baby Huey Join Date: Aug 2020 Location: Missouri Posts: 22	Just a suggestion. Make sure that you don't have a vacuum leak on the intake manifold. I think that I remember Motocheese finding that his carb didn't seal properly until he added some washers to the mounting bolts.
	1

09-08-2020, 12:33 AM	#15
aaw611 Join Date: Jun 2020 Posts: 48	That main jet sounds wayyy huge. Any of the idle/choke issues are going to be related to the pilot jet. That's what you should be focusing on in my opinion.
	2