Honda TRX250R Forums banner
1 - 20 of 31 Posts

·
Registered
Joined
·
722 Posts
Discussion Starter · #1 ·
Well we finally took our 370 pro cross motor to the dyno today. Has a Sherear out of frame drag pipe, 44 alky lectron, direct drive lock up clutch, and one of our new programable CR igntions that we have been developing. We made 77.5 HP and 48 ft lbs of torque. i have the graph but its way small, ill try to make it bigger. It makes over 70 hp in a 1600 rpm range and over 75 hp over 900 rpm. should be a very fast bike!
 

·
Registered
Joined
·
722 Posts
Discussion Starter · #4 ·
right now,my expectations are a bit jaded??? LOL it will make 1 pass up the hill or down a 300 ft track and then it will need to be parked to let cool. The motor builds alot of heat due to the size of the stinger. The stinger on the sherear pipe is just to small, so the motor relies on lots of fuel and alot of timing...we will be putting a larger stinger on the pipe, and re cutting another dome. Then it should be very very reliable, and we are expecting to see 80-82 hp on the dyno, all motor!
 

·
Registered
Joined
·
722 Posts
Discussion Starter · #7 ·
This cyl was done by Nate McCoy, 65-70 would be no problem in my eyes out of a 330. .....and yes that was on alky
 

·
Registered
Joined
·
2,042 Posts
We made 77.5 HP and 48 ft lbs of torque. i have the graph but its way small, ill try to make it bigger. It makes over 70 hp in a 1600 rpm range and over 75 hp over 900 rpm. should be a very fast bike!
Is that correct? 70hp at 1600 rpm? I assume the 75 hp is at 9000, not 900.
 

·
Registered
Joined
·
17 Posts
he is saying that it has over 70 hp through a range of 1600 rpm. meaning from like 6000-7600 rpm it has over 70 hp. (Obviously i dont know the exact rpm range so that just an example) and over 75 hp in a 900 rpm range.
 

·
Registered
Joined
·
722 Posts
Discussion Starter · #11 ·
he is saying that it has over 70 hp through a range of 1600 rpm. meaning from like 6000-7600 rpm it has over 70 hp. (Obviously i dont know the exact rpm range so that just an example) and over 75 hp in a 900 rpm range.
Yes that is correct!!!! it is still making power at 9200.......and i do have a 2-4 over ride trans in it...
 

·
Premium Member
Joined
·
4,273 Posts
That heating problem though, you got to deal with that big time.
Sitting on the side cooling & everybody else still running, I dont know about all that cause you know what the others running that day will be thinking. Thats how dragging is, bunch of talk till they got to pay :eek: .
Neil
 

·
Registered
Joined
·
722 Posts
Discussion Starter · #16 ·
Yes 86 i do know how to cut them....LOL its not har just takes time...the 2-4 are easy, the 1-4 are a little bit tougher....

Neil, yes we do need to deal with it some how..?? LOL It makes me a bit nervous...the stinger on the sherear pipe is just too small. we had to crank up the timing with our new programbale ignition to try to keep it cool, as well as drilling the power jet serveral times trying to give it more fuel...We had a serious water pump leak as well, but it was not water coming out..LOL i forgot to put the oil seal between the bearing and the mechanical seal... I fixed that and put straight water and redline water wetter in instead of coolant, and it seems to be staying a bit cooler...its crazy to think 130 deg is hot tho isnt it! LOL it shouldnt get over 110 on methanol...
 

·
Registered
Joined
·
2,042 Posts
That is well over 3 hp per cubic inch. In the automotive world, that is considered a ton of horsepower. That would be like a 350 ci chevy making 1050 hp. 2 strokes are awesome!!!

1 cubic inches = 16.387064 cubic centimeters
370 (cubic centimeters) = 22.5787853 cubic inches
 

·
Registered
Joined
·
499 Posts
I doubt you can get low 70 hp out of a 330 but in the low to mid 60's for sure. Add a 4 mil stroke to the 330 with the right carb/pipe combo and I think you could get close. It's going to be a top end screemer to get there but it can be done I believe. I had a 370 do 65 HP and 44 ft lb's of torque making it's power at 7500 rpms. it was the crappy LRD big bore pipe I had on it. With a better all around pipe and a bit more tuning I feel 70 would have been real close. I just need 1,000 to 1500 rpm more to get there.
 

·
Registered
Joined
·
2,042 Posts
Blasterman, I thought you were building a Puma. Any progress?
 
1 - 20 of 31 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top