max rpms CSC tt250

elkhunter338 · 08-10-2022, 11:50 PM

Manual states max. hp at 7k. I have 3,000 miles on the bike so it's well broke in. I upgraded the carb with the off road jets to get some more fuel. Now the bike will run 9k+ I stopped at 9,000 rpms. The tach on the bike shows red line at 10,500.
With factory jets it struggled to run to 7,500 rpms.

What is a max sustained rpm for running down the hwy?
What a good max rpm for shifting?

TT250 from CSC

So far 3 years later, 3,000 miles. 1 turn signal wiring issue and a battery. I don't want to blow the engine up with too high of revs.

Megadan · 08-11-2022, 06:33 AM

Not too much point going past 8000rpm with these engines really. You can usually do so in the lower gears because the gearing allows it to pull that quickly but the power falls off pretty quickly past 8000 which is why these bikes tend to be limited to top speeds around 65-70 (if the sprockets on it allow it to do so).

Max sustained RPM... I've been running my Hawk down the highway for years cruising along at 6000-7000rpm and it hasn't blinked an eye.

**JerryHawk250** · 08-11-2022, 07:49 AM

Megadan is right. These CG pushrod engines aren't designed for high rpm's but will give you plenty of low end grunt. The CB OHC type engines like on my KPX250, X22R and Ghost 250 will easily go past 10,000 rpm but still only make there max HP at around the 7500-8000 rpm range.

flopsweat · 08-11-2022, 08:14 AM

I was wondering this myself. After my initial 500mi break in, I started giving it some more oomph when I accelerated, and found that shifting somewhere in the 6k rpm range feels the smoothest. I don't believe I've ran it over 8k, as I felt like it was just screaming with little power, so it's good to know there's not much point with these engines.

As for sustained rpm, also good to know I can buzz down at 60mph for a good while without worrying. I've got a camping trip next week (4hr ride), and another 4hr ride a couple weeks after that planned, which will be the first time I'll be holding her at 55mph+ for most of the way.

buzz · 08-11-2022, 09:53 PM

you'll be fine, 3000 miles and no troubles. TBR7 Chinariders rule

elkhunter338 · 08-12-2022, 10:43 PM

Quote:

Originally Posted by flopsweat

I was wondering this myself. After my initial 500mi break in, I started giving it some more oomph when I accelerated, and found that shifting somewhere in the 6k rpm range feels the smoothest. I don't believe I've ran it over 8k, as I felt like it was just screaming with little power, so it's good to know there's not much point with these engines.

As for sustained rpm, also good to know I can buzz down at 60mph for a good while without worrying. I've got a camping trip next week (4hr ride), and another 4hr ride a couple weeks after that planned, which will be the first time I'll be holding her at 55mph+ for most of the way.

if you don't have DEQ checks, the off road carb. jet kit is a good upgrade. Mine would barely rev. 7,500 rpms. With the carb jet kit it will rev. 9,000 rpms.

elkhunter338 · 08-12-2022, 10:46 PM

My situation is different gearing than most folks are running. I am geared low with a larger rear sprocket for mainly trail riding. Mine runs. 6,000 rpms at 40 mph. On occasion when I am on paved roads for 10-15 min I kind of need to run 50 mph to keep up with traffic. I can run 50 mph at 8,200 rpms, but I don't want to blow the engine. Short periods of time 10-15 min. then I am back on the dirt roads at slower speeds.
Thus my questions.

08-10-2022, 11:50 PM	#1
elkhunter338 Join Date: Dec 2018 Location: Oregon Posts: 81	max rpms CSC tt250 Manual states max. hp at 7k. I have 3,000 miles on the bike so it's well broke in. I upgraded the carb with the off road jets to get some more fuel. Now the bike will run 9k+ I stopped at 9,000 rpms. The tach on the bike shows red line at 10,500. With factory jets it struggled to run to 7,500 rpms. What is a max sustained rpm for running down the hwy? What a good max rpm for shifting? TT250 from CSC So far 3 years later, 3,000 miles. 1 turn signal wiring issue and a battery. I don't want to blow the engine up with too high of revs.
	1

08-11-2022, 06:33 AM	#2
Megadan Join Date: Apr 2017 Location: Omaha, NE Posts: 8,061	Not too much point going past 8000rpm with these engines really. You can usually do so in the lower gears because the gearing allows it to pull that quickly but the power falls off pretty quickly past 8000 which is why these bikes tend to be limited to top speeds around 65-70 (if the sprockets on it allow it to do so). Max sustained RPM... I've been running my Hawk down the highway for years cruising along at 6000-7000rpm and it hasn't blinked an eye. __________________ 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
	2

08-11-2022, 07:49 AM	#3
JerryHawk250 Moderator Join Date: Oct 2016 Location: Houma, La. Posts: 11,590	Megadan is right. These CG pushrod engines aren't designed for high rpm's but will give you plenty of low end grunt. The CB OHC type engines like on my KPX250, X22R and Ghost 250 will easily go past 10,000 rpm but still only make there max HP at around the 7500-8000 rpm range. __________________ 2023 Lifan Lycan 250 Chopper 2023 Venom Evader 2022 Lifan KPX250 2020 Kawasaki Vulcan S (Sold) 2004 Honda ST 1300 2016 Black Hawk 250 (sold) Keihin PE30 carb,125 main,38 slow.Pod filter,ported & decked head 10:1 CR,Direct Ignition Coil,15/40Sprockets,NGK DPR8EIX-9,De-Cat,Dual Oil Cooler,Digital Cluster 2016 Cazador180 XL 2014 Coolster150 JerryHawk250.com My YouTube Channel
	1

08-11-2022, 08:14 AM	#4
flopsweat Join Date: Oct 2021 Location: The burbs of Chicago Posts: 237	I was wondering this myself. After my initial 500mi break in, I started giving it some more oomph when I accelerated, and found that shifting somewhere in the 6k rpm range feels the smoothest. I don't believe I've ran it over 8k, as I felt like it was just screaming with little power, so it's good to know there's not much point with these engines. As for sustained rpm, also good to know I can buzz down at 60mph for a good while without worrying. I've got a camping trip next week (4hr ride), and another 4hr ride a couple weeks after that planned, which will be the first time I'll be holding her at 55mph+ for most of the way.
	1

08-11-2022, 09:53 PM	#5
buzz Join Date: Dec 2020 Location: Dayton Pa. Posts: 880	you'll be fine, 3000 miles and no troubles. TBR7 Chinariders rule
	0

08-12-2022, 10:46 PM	#7
elkhunter338 Join Date: Dec 2018 Location: Oregon Posts: 81	My situation is different gearing than most folks are running. I am geared low with a larger rear sprocket for mainly trail riding. Mine runs. 6,000 rpms at 40 mph. On occasion when I am on paved roads for 10-15 min I kind of need to run 50 mph to keep up with traffic. I can run 50 mph at 8,200 rpms, but I don't want to blow the engine. Short periods of time 10-15 min. then I am back on the dirt roads at slower speeds. Thus my questions.
	0