NSR250.net Forums Logo: Honda NSR 250 Forums, Classifieds and Service Manual in English. Covering All Honda NSR 250 MC16, MC18, MC21 and MC28 models
NSR250.net Forums

#
 
#
 
Performance Engineering

  • NSR250 Forums Index ‹ NSR250R Discussion
  • Members Content
  • Members Garage
  • Subscription
  • Transactions
  • FAQ
  • Search
  • Register
  • Log in

wont rev out under load!!!!!!!!!!!!


Reply to topic   printer-friendly view
Page 1 of 1   Download Topic





Hazey

 
Posts: 21
Joined: 14 Nov 2009

Location: WestMidlands
    Send private message View user's profile
    Reply with quote  

wont rev out under load!!!!!!!!!!!!

Thu Oct 20, 2011 8:30 pm » Post: #1 » Download Post

Can anyone help?? I have built a track bike using a heavily ported mc16 motor as the basis, sadly im still using the mc16 ignition, i have stripped the loom down to basics and it runs great, until you ride it!! it wont rev out at all under any load, i did have some cdi issues! It killed 2 cdi units before i tracked down the problem to the power valve controller. How ever i have removed the controller and servo motor and lock wired the valves open. does any one have any ideas? im well and truely stuck now!! Maybe the cdi units need to sense the servo and controller in place to work properly????? or does any one have a mc 18/21 ignition set hanging about????
_________________
Thanks.......!
Back to top


fontyyy

 
Posts: 3509
Joined: 10 Apr 2004

Location: Derbyshire, England
1991 Honda NSR250 MC21
    Send private message View user's profile Visit poster's website MSN Messenger
    Reply with quote  

Thu Oct 20, 2011 8:44 pm » Post: #2 » Download Post

I can't speak for the MC16 but the (PGM-II) mc18 works fine with the RC valves unplugged and lockwired wired open....I have the race results to prove it.

I'd guess it's either jetted so far out as to not run properly or the HT side is breaking down.
_________________
Please do not PM me technical questions, if you can't find it on the Forum start a thread
Back to top


toneless

 
Posts: 178
Joined: 02 Aug 2010

Location: Athens, Greece
    Send private message View user's profile Visit poster's website
    Reply with quote  

Re: wont rev out under load!!!!!!!!!!!!

Thu Oct 20, 2011 10:58 pm » Post: #3 » Download Post

Hazey wrote:...until you ride it!! it wont rev out at all under any load...


Doesn't sound like an issue caused from the CDI.
Are you using carbs from a later model? Rolling Eyes
_________________
2t-racelab.com
Back to top


Hazey

 
Posts: 21
Joined: 14 Nov 2009

Location: WestMidlands
    Send private message View user's profile
    Reply with quote  

Fri Oct 21, 2011 7:52 pm » Post: #4 » Download Post

i tried mc 18 carbs but they were in very poor condition so im back on the mc16 carbs, was gonna try some rgv carbs on it as the jets are readily available!!!
_________________
Thanks.......!
Back to top


anonymous.shyster
Supporter - Carbon
Supporter - Carbon
 
Posts: 537
Joined: 09 Nov 2008

Location: Australia
    Send private message View user's profile
    Reply with quote  

Sat Oct 22, 2011 1:21 pm » Post: #5 » Download Post

How far open did you wire the powervalves? I know that having them too far open actually starts to close the exhaust port off again, so you really have to look inside the ports or at the very least don't go past where the fully open punch marks are on the butterfly and cylinder.
_________________
MC21 Honda NSR250. TYGA 300 conversion.
Back to top


Reply to topic   printer-friendly view
Page 1 of 1   Download Topic

NSR250R Discussion

You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You cannot attach files in this forum
You cannot download files in this forum

  • NSR250 Forums Index
  • All times are GMT
Powered by phpBB © 2001, 2005 phpBB Group


Hosted by NSR250dotNET © 2008 NSR250dotNET