Hawk tune up, top speed, and general musings.

OneLeggedRider · 05-28-2019, 04:05 PM

Well it's coming up on 600 miles so I figured I was past the break in tune up time. The valves and chain were loose, and oil change was long overdue, and the muffler was rubbing the tire at full suspension compression.

The muffler was simple, just a trip to the hardware store for a longer bolt and 5 washers. The 520 O-ring chain had stretched alot, I was actually concerned about riding it lastnight. But 2 turns on each adjustment screw fixed that. The oil was remarkably clean, I figured it would have a gray color, and there wasn't any metal in the screen. So I'm real happy about that.

I had set the valves at .005" for the break in and I figured they'd be tighter now but they were actually looser. I set them to .003" and hopefully won't have to worry them for a while. I also added 1 washer to the carb needle for a total of 3, but haven't test ridden it yet. One of the intake nuts fell down into the sprocket cover so I had to pull the shifter and cover off to retrieve it.

Yesterday I checked the top speed with GPS and the stock speedometer is way off. In the heat of the day it ran 58mph and 63mph in the cool night air. Also I'm impressed with the brakes. I popped over a hill on an unfamiliar paved road and had about 30 feet to turn right or left, so I locked up the rear wheel momentarily and grabbed a handful of front brake! There might be a small hole in the seat from my sphincter tightening up..

**JerryHawk250** · 05-28-2019, 04:41 PM

She's running pretty good considering you are geared low.

So how's the new leg training going? I'm still amazed at the technology.

OneLeggedRider · 05-28-2019, 06:12 PM

Quote:

Originally Posted by JerryHawk250

She's running pretty good considering you are geared low.

So how's the new leg training going? I'm still amazed at the technology.

I'm not running out of gear at all, running out of power. This thing makes nothing on the top end. I can actually take off faster by not letting the gears wind out.

The leg is doing great, when it learns a new activity it never forgets it. And just like the Cyberdine Systems technology it can't be shut off, I can power it down but it's still on and still recording. If it learns how to charge itself we're all in trouble..

nij_tp · 05-28-2019, 04:44 PM

What is the app you are using (is it Live mobile location and ...... or is that something they are trying to sell you)?

OneLeggedRider · 05-28-2019, 06:05 PM

Quote:

Originally Posted by nij_tp

What is the app you are using (is it Live mobile location and ...... or is that something they are trying to sell you)?

Just says "GPS Speedometer" on Google play store.

Megadan · 05-28-2019, 06:42 PM

From my experiences, even though the engines do tend to mostly break in around the 500 mile mark, it can take upwards of 1000 or so before everything is fully broken in. Especially on that last little bit of top end. Even so, what Jerry said, and what you said, are both accurate. You ran out of gear because you are running past the powerband via RPM. If you went even taller out back it would pick up more top speed by shifting where you are sitting in the RPM range in 5th. Stepping down from a 45 to a 43 rear on my last Hawk made a big difference in top speed by placing the RPMs lower into the stronger part of the power curve at those given speeds. You do start to notice a good hit in the acceleration department

Even though my head porting opened up a bit on the upper end of the rev range, I can tell that the carb size is a small limiting factor, but the cam profile is still going to keep this motor a bit flat on the top end. That is why I can run up to the 65-70mph mark usually with little effort, but the 70-75 range it starts to fall off and struggle, and anything past 75 takes a total planetary alignment and perfect conditions. If I geared up a bit more it is likely my top speed would change very little, but how it pulled at those speeds would be very different. I just don't want to lose the acceleration that I do have in the lower gears to achieve that.

I am considering seeing what it takes to make a 14 tooth front work. I know the 13 tooth is a bit tight, but unlike a 17t 428 sprocket and chain, I can still remove and install my sprocket cover with ease. That tells me there is a little room to play with, and I have no issue removing material from it if it will allow it to fit. That would open up the door to front sprocket swaps so I can easily change between road only and better off road gearing.

OneLeggedRider · 05-28-2019, 07:25 PM

Well I know I'm not changing that 33 tooth rear sprocket until it's absolutely necessary lol. But I will go ahead and order a 13 tooth front sprocket just to see if I like it. I haven't been off roading it as much as I thought I would and first gear is really low, I have to shift into second after just a few feet. Damn thing should come with a 6 speed transmission.

Also the seat has gotten more comfortable for me because I'm making myself sit further forward, feels like I'm sitting on the handlebars though.

Gonna test ride the carb needle change in just a few, it was just too damn hot out there. 86° and really humid.

OneLeggedRider · 05-28-2019, 09:01 PM

The verdict is still out on adding a 3rd washer to the needle. Just took it for a little spin and really couldn't tell any difference at all. Guess I'll have to take it for a longer ride tomorrow and see if it affected top speed, plug color etc.

OneLeggedRider · 06-03-2019, 04:28 AM

Well the verdict is in on the 3.5 washers. Due to inclement girlfriends and nasty weather I hadn't gotten a chance to go for a long ride until yesterday. I think I've found the sweet spot. It's running better than ever now. No hesitation off idle and pulls strong throughout the midrange. The valve adjustment probably helped some too. I haven't had a chance to do plug readings, but the pipe is putting off less heat and the snap crackle pop on deceleration is almost completely gone.

I got the idea from I believe MyBike? The guy with the customized Magician. He put 4 washers on the needle and didn't go really big on the main jet, and raves about how well it runs. The reason I say 3.5 washers is because the local hardware didn't have the thinner washers I originally bought and this one is about 1.5 times thicker.

So with lots of trial and error I'm at .45mm pilot jet, 3.5 washers on the needle, and a 110 main jet with 2 turns on the mixture screw. And it's really running well, the exhaust note even sounds a little different if that makes any sense. Now should I drill the pilot to .5mm, or put it on the shelf and start over with the Mikuni clone?.. Hahaha!

NzBrakelathes · 06-03-2019, 07:59 AM

Quote:

Originally Posted by OneLeggedRider

Well the verdict is in on the 3.5 washers. Due to inclement girlfriends and nasty weather I hadn't gotten a chance to go for a long ride until yesterday. I think I've found the sweet spot. It's running better than ever now. No hesitation off idle and pulls strong throughout the midrange. The valve adjustment probably helped some too. I haven't had a chance to do plug readings, but the pipe is putting off less heat and the snap crackle pop on deceleration is almost completely gone.

I got the idea from I believe MyBike? The guy with the customized Magician. He put 4 washers on the needle and didn't go really big on the main jet, and raves about how well it runs. The reason I say 3.5 washers is because the local hardware didn't have the thinner washers I originally bought and this one is about 1.5 times thicker.

So with lots of trial and error I'm at .45mm pilot jet, 3.5 washers on the needle, and a 110 main jet with 2 turns on the mixture screw. And it's really running well, the exhaust note even sounds a little different if that makes any sense. Now should I drill the pilot to .5mm, or put it on the shelf and start over with the Mikuni clone?.. Hahaha!

Why not buy the simple “first tune kit” and or go to a pumper carb using same type of carb
Both are more economical then changing to mikuni and pumper gives a gain st only a little more $

https://rover.ebay.com/rover/0/0/0?m...2F303077495104

https://rover.ebay.com/rover/0/0/0?m...2F303169447550

dpl096 · 06-04-2019, 08:54 PM

Damn it Dan.... That stuff is disgusting..,. Puke

Merlin · 06-04-2019, 09:01 PM

Perhaps this is more to your liking:
https://www.dailymotion.com/video/x2hwqlw

OneLeggedRider · 06-05-2019, 12:07 AM

Took the bike out for 3 hours tonight, and I have definitely got the carb right. This thing is pulling so hard, idling so well, starting so good, etc.. It did stall on me one time in town because of clutch fade, but I know an oil cooler will fix that. And I'm gonna order a 13 tooth front sprocket for more speed, I can always switch sprockets if I'm going riding at the Reclaim. Also figured out 5 washers on the muffler wasn't quite enough, but I can live with it barely touching at full suspension compression. Loving this bike!

OneLeggedRider · 06-05-2019, 10:31 AM

I forgot to include this about cold starting. With a. 45mm pilot and 3.5 washers on the needle it's getting plenty of fuel. At 75° I don't need the choke at all, and if I do put it on half choke I have to take the choke off immediately, and if I try full choke it will start but acts like it's drowning, I think I almost fouled the plug lol. And I really paid attention to the deceleration yesterday, I kinda miss the snap crackle pop.

mybike · 06-05-2019, 09:12 PM

Quote:

Originally Posted by OneLeggedRider

I forgot to include this about cold starting. With a. 45mm pilot and 3.5 washers on the needle it's getting plenty of fuel. At 75° I don't need the choke at all, and if I do put it on half choke I have to take the choke off immediately, and if I try full choke it will start but acts like it's drowning, I think I almost fouled the plug lol. And I really paid attention to the deceleration yesterday, I kinda miss the snap crackle pop.

I also need no choke down to 60 65 degrees. Bike starts real fast, in fact lately have been kick starting it because only needs one kick and boom fires right up.

Nice when they run right. And yes when tuned right these little engines pull pretty hard for what they are.

Enjoy your ride leg.

05-28-2019, 04:05 PM	#1
OneLeggedRider Join Date: Nov 2018 Location: Stockport, Oh. Posts: 1,442	Hawk tune up, top speed, and general musings. Well it's coming up on 600 miles so I figured I was past the break in tune up time. The valves and chain were loose, and oil change was long overdue, and the muffler was rubbing the tire at full suspension compression. The muffler was simple, just a trip to the hardware store for a longer bolt and 5 washers. The 520 O-ring chain had stretched alot, I was actually concerned about riding it lastnight. But 2 turns on each adjustment screw fixed that. The oil was remarkably clean, I figured it would have a gray color, and there wasn't any metal in the screen. So I'm real happy about that. I had set the valves at .005" for the break in and I figured they'd be tighter now but they were actually looser. I set them to .003" and hopefully won't have to worry them for a while. I also added 1 washer to the carb needle for a total of 3, but haven't test ridden it yet. One of the intake nuts fell down into the sprocket cover so I had to pull the shifter and cover off to retrieve it. Yesterday I checked the top speed with GPS and the stock speedometer is way off. In the heat of the day it ran 58mph and 63mph in the cool night air. Also I'm impressed with the brakes. I popped over a hill on an unfamiliar paved road and had about 30 feet to turn right or left, so I locked up the rear wheel momentarily and grabbed a handful of front brake! There might be a small hole in the seat from my sphincter tightening up.. Last edited by OneLeggedRider; 10-30-2019 at 01:58 AM.
	2

05-28-2019, 04:41 PM	#2
JerryHawk250 Moderator Join Date: Oct 2016 Location: Houma, La. Posts: 11,850	She's running pretty good considering you are geared low. So how's the new leg training going? I'm still amazed at the technology. __________________ 2025 Lifan KPT 400 2024 Linhai 300 ATV 4x4 2023 Lifan Lycan 250 Chopper 2023 Venom Evader 2022 Lifan KPX250 2020 Kawasaki Vulcan S (Sold) 2004 Honda ST 1300 (Sold) 2016 Black Hawk 250 (sold) 2016 Cazador180 XL 2014 Coolster150 JerryHawk250.com My YouTube Channel
	0

05-28-2019, 04:44 PM	#4
nij_tp Join Date: Apr 2019 Location: Amherst NH Posts: 105	What is the app you are using (is it Live mobile location and ...... or is that something they are trying to sell you)? __________________ Toys include Audi B7, running Stage 2+, S4 Brakes. My VW Vanagon is running 2.5l VVT Subaru engine, 18" AMG wheels, Porsche 944 Steering Wheel, W eekender interior. 1989 VW Vanagon Bluestar one of 2500, 1986 Honda Shadow, 2000 Suzuki Intruder, 1988 Kawasaki Voyager XII, 1976 Mercury Capri II, a bunch of Trailers including a shortened Vanagon for camping, a Sequoia and the latest addition a 2019 Hawk 250. (But dont tell the wife! ) (Latest latest addition a 1995 fwd Subaru SVX)
	0

05-28-2019, 06:42 PM	#6
Megadan Join Date: Apr 2017 Location: Omaha, NE Posts: 8,147	From my experiences, even though the engines do tend to mostly break in around the 500 mile mark, it can take upwards of 1000 or so before everything is fully broken in. Especially on that last little bit of top end. Even so, what Jerry said, and what you said, are both accurate. You ran out of gear because you are running past the powerband via RPM. If you went even taller out back it would pick up more top speed by shifting where you are sitting in the RPM range in 5th. Stepping down from a 45 to a 43 rear on my last Hawk made a big difference in top speed by placing the RPMs lower into the stronger part of the power curve at those given speeds. You do start to notice a good hit in the acceleration department Even though my head porting opened up a bit on the upper end of the rev range, I can tell that the carb size is a small limiting factor, but the cam profile is still going to keep this motor a bit flat on the top end. That is why I can run up to the 65-70mph mark usually with little effort, but the 70-75 range it starts to fall off and struggle, and anything past 75 takes a total planetary alignment and perfect conditions. If I geared up a bit more it is likely my top speed would change very little, but how it pulled at those speeds would be very different. I just don't want to lose the acceleration that I do have in the lower gears to achieve that. I am considering seeing what it takes to make a 14 tooth front work. I know the 13 tooth is a bit tight, but unlike a 17t 428 sprocket and chain, I can still remove and install my sprocket cover with ease. That tells me there is a little room to play with, and I have no issue removing material from it if it will allow it to fit. That would open up the door to front sprocket swaps so I can easily change between road only and better off road gearing. __________________ Hawk Information and Resource guide: http://www.chinariders.net/showthread.php?t=20331 2018 Hawk 250 - Full Mod list here. http://www.chinariders.net/showpost....62&postcount=1 2024 Royal Enfield Shotgun 650 https://chinariders.net/showthread.php?t=34124
	1

06-03-2019, 04:28 AM	#9
OneLeggedRider Join Date: Nov 2018 Location: Stockport, Oh. Posts: 1,442	Well the verdict is in on the 3.5 washers. Due to inclement girlfriends and nasty weather I hadn't gotten a chance to go for a long ride until yesterday. I think I've found the sweet spot. It's running better than ever now. No hesitation off idle and pulls strong throughout the midrange. The valve adjustment probably helped some too. I haven't had a chance to do plug readings, but the pipe is putting off less heat and the snap crackle pop on deceleration is almost completely gone. I got the idea from I believe MyBike? The guy with the customized Magician. He put 4 washers on the needle and didn't go really big on the main jet, and raves about how well it runs. The reason I say 3.5 washers is because the local hardware didn't have the thinner washers I originally bought and this one is about 1.5 times thicker. So with lots of trial and error I'm at .45mm pilot jet, 3.5 washers on the needle, and a 110 main jet with 2 turns on the mixture screw. And it's really running well, the exhaust note even sounds a little different if that makes any sense. Now should I drill the pilot to .5mm, or put it on the shelf and start over with the Mikuni clone?.. Hahaha! Last edited by OneLeggedRider; 10-30-2019 at 01:58 AM.
	1

05-28-2019, 07:25 PM	#7
OneLeggedRider Join Date: Nov 2018 Location: Stockport, Oh. Posts: 1,442	Well I know I'm not changing that 33 tooth rear sprocket until it's absolutely necessary lol. But I will go ahead and order a 13 tooth front sprocket just to see if I like it. I haven't been off roading it as much as I thought I would and first gear is really low, I have to shift into second after just a few feet. Damn thing should come with a 6 speed transmission. Also the seat has gotten more comfortable for me because I'm making myself sit further forward, feels like I'm sitting on the handlebars though. Gonna test ride the carb needle change in just a few, it was just too damn hot out there. 86° and really humid.
	0

05-28-2019, 09:01 PM	#8
OneLeggedRider Join Date: Nov 2018 Location: Stockport, Oh. Posts: 1,442	The verdict is still out on adding a 3rd washer to the needle. Just took it for a little spin and really couldn't tell any difference at all. Guess I'll have to take it for a longer ride tomorrow and see if it affected top speed, plug color etc.
	1

06-04-2019, 08:54 PM	#11
dpl096 Join Date: Sep 2015 Location: East Central Hellinois Posts: 1,344	Damn it Dan.... That stuff is disgusting..,. Puke __________________ ************************************************ * " Time you enjoy wasting, is not wasted." - John Lennon “I predict future happiness for Americans, if they can prevent the government from wasting the labors of the people under the pretense of taking care of them.” ― Thomas Jefferson "If you don't know where you're going any road will take you there" ....George Harrison song
	0

06-04-2019, 09:01 PM	#12
Merlin Join Date: Jun 2016 Location: Colorado Posts: 1,107	Perhaps this is more to your liking: https://www.dailymotion.com/video/x2hwqlw __________________ Bashan Blaze Mods: Alloy Rim's, Muffler, Mukuni VM26 Carb, Foam Filter, Tachometer, Volt Meter,LED Headlight, LED Blinkers
	3

06-05-2019, 12:07 AM	#13
OneLeggedRider Join Date: Nov 2018 Location: Stockport, Oh. Posts: 1,442	Took the bike out for 3 hours tonight, and I have definitely got the carb right. This thing is pulling so hard, idling so well, starting so good, etc.. It did stall on me one time in town because of clutch fade, but I know an oil cooler will fix that. And I'm gonna order a 13 tooth front sprocket for more speed, I can always switch sprockets if I'm going riding at the Reclaim. Also figured out 5 washers on the muffler wasn't quite enough, but I can live with it barely touching at full suspension compression. Loving this bike!
	3

06-05-2019, 10:31 AM	#14
OneLeggedRider Join Date: Nov 2018 Location: Stockport, Oh. Posts: 1,442	I forgot to include this about cold starting. With a. 45mm pilot and 3.5 washers on the needle it's getting plenty of fuel. At 75° I don't need the choke at all, and if I do put it on half choke I have to take the choke off immediately, and if I try full choke it will start but acts like it's drowning, I think I almost fouled the plug lol. And I really paid attention to the deceleration yesterday, I kinda miss the snap crackle pop.
	3

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