CBR 1100XX "Super Blackbird" 1998 - 2003 CBR 1000XX

High idle rpm from cold start

  #1  
Old 01-14-2019, 06:45 AM
Junior Member
Thread Starter
Join Date: Jan 2019
Posts: 4
Unhappy High idle rpm from cold start

Hi, novice but learning mechanic in need of more experienced riders advice. I bought an 02 Blackbird in December and had to replace downpipes (blowing in the collector box area to bad to repair). After a lot of hassles, downpipes/mufflers not off bike since new in 02!, finally got a replacement set of 04 downpipes and mufflers on yesterday. The bike has not been started and radiator off for nearly six weeks to allow the replacements time to arrive. Flushed radiator and filled with new coolant, after very careful repeated starts of the engine in 15 - 20 second bursts as rpm started at 3000'sh and slightly rose as the time went on, topping up radiator only after each burst of engine on (not reservoir, this is still empty). Bike temp gauge showed a rise to about 45 degrees Celsius as coolant was warming up but decided, as idle speed not dropping and still creeped up to about 3500 rpm, to stop any more engine bursts until I get advice??

Jobs done to bike since December:

1. Changed downpipes and muffler to ones from different 04 bikes
2. Radiator off for about 6 weeks and engine/radiator flushed with distilled water (came out virtually clean clear colour with no crud) before refilling with new coolant
3. Throttle side Heated grip replaced (old one not working) and throttle body seems to fully rotate and close
4. Sprayed all cables and parts under tank with AC50.
5. Replaced o2 Sensor with a new aftermarket (Walkers) one as could not get old one out of old mufflers
6. Cleaned up and rubbed down flaking engine paintwork and repainted with Hammerite.

Bike has 36500 miles on clock.

Not sure what I have done in changing the above to cause the idle speed to stay above 3000 rpm and could do with some advice on things to try before starting bike up again. Also am I likely to do any damage to engine/coolant system if I let the bike run up to water temperature with radiator cap on (off at moment whilst I refilled with new coolant) if idle speed stays at or slightly above 3000 rpm for the 3-5 minutes to do so??

Any advice would be great.

P.S. Someone has already suggested spraying the Wax element unit with WD40 and hand massaging it before starting up again but would also be keen to hear of other ideas and potential damage avoidance, thanks.
 
  #2  
Old 01-14-2019, 06:58 AM
74demon's Avatar
Administrator and MVN, March 2012/Oct 2013 ROTM
Join Date: Sep 2011
Location: socal 949/951
Posts: 7,686
Default

Could have an air pocket in the cooling system or that coolant isn't flowing through the wax unit. It needs to have warm coolant to bring down the idle speed.
 
  #3  
Old 01-14-2019, 09:43 AM
Junior Member
Thread Starter
Join Date: Jan 2019
Posts: 4
Default

Thanks for feedback, as you say I would like to get coolant up to running temperature to see if this helps to clear any air pockets etc. but just concerned running bike with no load at 3000+ rpm for several minutes before trying anything else potentially less damaging. Regards, David.
 
  #4  
Old 01-14-2019, 10:32 AM
74demon's Avatar
Administrator and MVN, March 2012/Oct 2013 ROTM
Join Date: Sep 2011
Location: socal 949/951
Posts: 7,686
Default

It wont hurt a thing. 3,000 rpm is like idle on these motors.
 
  #5  
Old 01-14-2019, 10:42 AM
Junior Member
Thread Starter
Join Date: Jan 2019
Posts: 4
Default

Ok fingers crossed for tomorrows try of all advice so far, including yours Demon
 
  #6  
Old 01-15-2019, 05:52 AM
Junior Member
Thread Starter
Join Date: Jan 2019
Posts: 4
Default

[COLOR=left=#222222]Hi all, firstly thanks for feedback and advice much appreciated. Before I went through with checking wax element / throttle cable etc. bike had been stood for about 36 hours with radiator cap off to hopefully bleed out any trapped air. Topped up radiator and put coolant in reservoir this time, put radiator cap on and started bike (someone said wax element reacts to warm coolant so thought I would risk high revs initially to get warm coolant around pipework). Didn't need to worry as for whatever reason bike started first press of switch went to idle at about 2000 rpm and after around a couple of minutes idle had dropped back to 1200 which is fine to me. Let bike then carry on idling, with occasional throttle twist to 4000 rpm, warming coolant up to 100 degrees Celsius on temp gauge, to check fan kicked in, which it did. Switched off, let bike cool down for 40 mins and topped radiator up, very little needed, started bike up again and let temp get up to 100 degrees again, fan kicked. So thanks again but hopefully this part of the project is now working fine. Have tightened up all nuts on downpipes/mufflers/clamps as warmth seemed to allow this. Just got the fun of refitting all cowls/fairings back in place for the first time![/COLOR]=left

[COLOR=left=#222222]Now for the next part of the project, changing all [/COLOR][COLOR=left=#222222]brake lines to HEL s/s braided hoses![/COLOR]

[COLOR=left=#222222]Kind regards[/COLOR]

[COLOR=left=#222222]David[/COLOR]
 
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Gnarly 928
General Tech
4
03-28-2013 12:07 PM
SPR-GRN
F4i - Main Forum
5
05-07-2012 06:08 PM
north
F4i - Main Forum
8
11-03-2011 11:34 PM
Slydell19
F4i - Main Forum
9
06-25-2010 03:39 PM
trixtrem
F4i - Main Forum
10
04-21-2006 08:58 AM


Thread Tools
Search this Thread
Quick Reply: High idle rpm from cold start


Advertising
Featured Sponsors
Vendor Directory

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

© 2019 MH Sub I, LLC dba Internet Brands

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.