1. This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.

Help Honda MC22 back from the Dead

Discussion in 'Honda 250cc In-line 4's' started by r1rmu13, May 13, 2018.

  1. Murdo

    Murdo The Good Doctor Staff Member Contributing Member Ride and Events Crew

    Messages:
    6,397
    Likes Received:
    4,786
    Trophy Points:
    1,148
    Joined:
    May 4, 2013
    Gender:
    Male
    Occupation:
    Retired
    Location:
    Tamworth, NSW
    My Bike:
    1937 Royal Enfield 250, CF Moto 250 V5, Honda's XL250, CBR250, FT500 plus a few others.
    You don't need to get it to run (I know that's your problem) but doing the timing light will see if your getting sparks at the right time of the compression stroke.
     
  2. r1rmu13

    r1rmu13 Member

    Messages:
    35
    Likes Received:
    12
    Trophy Points:
    18
    Joined:
    May 13, 2018
    Gender:
    Male
    Location:
    England
    My Bike:
    Honda Cbr250RR MC22
    I didn’t know you could do it spinning it over I thought you had to have the full RPM’s

    That certainly would help, going back many years since I have owned a timing light, I will pick one up tomorrow and give that s try

    Cheers thanks very much for your help ps there’s no way this is going to beat me
     
    • Like Like x 2
  3. Andych

    Andych Moderator Staff Member Premium Member Contributing Member Dirty Wheel Club

    Messages:
    4,289
    Likes Received:
    2,504
    Trophy Points:
    918
    Joined:
    Oct 6, 2016
    Gender:
    Male
    Location:
    Albury 2641
    My Bike:
    1987 Yamaha SRX250, Honda 1974 SL125 K1, 2022 Triumph Tiger Sport 660
    As long as you are getting spark the timing light will be a big help... just make sure you have a good battery source... I would use a jumper pack if you have one.. and dont spin it too long on the starter... they do get hot.. :)
     
  4. r1rmu13

    r1rmu13 Member

    Messages:
    35
    Likes Received:
    12
    Trophy Points:
    18
    Joined:
    May 13, 2018
    Gender:
    Male
    Location:
    England
    My Bike:
    Honda Cbr250RR MC22
    Yes I have a nice old Landy bat on hand, I take your point about over spinning things

    Any suggestions on what type of timing light to suit the MC22 inductive non ductive everthings a ductive 3 wire 2 wire?

    Cheers
     
  5. Andych

    Andych Moderator Staff Member Premium Member Contributing Member Dirty Wheel Club

    Messages:
    4,289
    Likes Received:
    2,504
    Trophy Points:
    918
    Joined:
    Oct 6, 2016
    Gender:
    Male
    Location:
    Albury 2641
    My Bike:
    1987 Yamaha SRX250, Honda 1974 SL125 K1, 2022 Triumph Tiger Sport 660
    Jeez.. it has been such a long time since I have used mine... it is inductive with a clip that goes over the plug lead.. plus it connects to 12 volt to boost the light source.. maybe you know someone who has one you can borrow rather than buying one specifically for this test... I know all about having to buy special tools just to do something that should be so simple..
     
  6. r1rmu13

    r1rmu13 Member

    Messages:
    35
    Likes Received:
    12
    Trophy Points:
    18
    Joined:
    May 13, 2018
    Gender:
    Male
    Location:
    England
    My Bike:
    Honda Cbr250RR MC22
    Yes mate I have gone for that type with dwell angle too, hopefully I will be able to confirm the cdi from this too

    Cheers
     
  7. Andych

    Andych Moderator Staff Member Premium Member Contributing Member Dirty Wheel Club

    Messages:
    4,289
    Likes Received:
    2,504
    Trophy Points:
    918
    Joined:
    Oct 6, 2016
    Gender:
    Male
    Location:
    Albury 2641
    My Bike:
    1987 Yamaha SRX250, Honda 1974 SL125 K1, 2022 Triumph Tiger Sport 660
    It has been several lifetimes since I have seen a dwell meter.. my timing light is just that.. timing light only.
    Dont expect to pick up any dwell angle info when you hook it up... lol
     
  8. kiffsta

    kiffsta Senior Member

    Messages:
    9,066
    Likes Received:
    6,872
    Trophy Points:
    1,168
    Joined:
    Aug 7, 2010
    Gender:
    Male
    Location:
    Brisbane
    So we know the fuel tap works, we know that your carbs are clean, and have new insulators , we know that your pickup coil is within spec , we know that the coils are firing and you have confirmed that there is spark.

    I assume your ignition switch is okay (sometimes wires come off at the back) , as you are getting spark, i also I also assume your kill/ start switch is working. Timing could be an issue as mentioned by the other members here , but I would be looking at your valves and making sure your clearances are within spec , tight valves will make the bike hard to start.

    If your clearances are good, then you could have an earth issue , try disconnecting and cleaning every connector in the harness. You could also try unplugging the stator and the voltage reg in case circuits are going to ground

    Pull your plugs , I’m betting they are black from repeated starting attempts and should be replaced , the only way to start these bikes cold is full choke and no throttle.

    Apart from that,’I am running out of ideas
     
  9. r1rmu13

    r1rmu13 Member

    Messages:
    35
    Likes Received:
    12
    Trophy Points:
    18
    Joined:
    May 13, 2018
    Gender:
    Male
    Location:
    England
    My Bike:
    Honda Cbr250RR MC22
    Hi there,

    I see you posted that today at 12 45 today, and haven’t looked at the site today, as I head my head buried in the bike checking valve clearances as I slept on it last night and came to the same conclusion

    2 Exhaust valve clearances are .19 ie out of spec 1 Exhaust on .20 bottom of spec

    I inlet at .18 so just in

    But I take your other points as very valid and if no starty then up and onwards

    Thanks very much for amount of thought you put into that cheers
     
  10. r1rmu13

    r1rmu13 Member

    Messages:
    35
    Likes Received:
    12
    Trophy Points:
    18
    Joined:
    May 13, 2018
    Gender:
    Male
    Location:
    England
    My Bike:
    Honda Cbr250RR MC22
    Here the update

    Worked late last night taken the cams out and removed the relevant shims

    Shins ordered for tonorrow, and arranged for a local engineering shop to grind down to mean

    With a bit of luck hoping the bike will ready for another try before the weekend

    Missed delivery for the timing light
     
  11. r1rmu13

    r1rmu13 Member

    Messages:
    35
    Likes Received:
    12
    Trophy Points:
    18
    Joined:
    May 13, 2018
    Gender:
    Male
    Location:
    England
    My Bike:
    Honda Cbr250RR MC22
    Hi guys,,

    Here’s the update as of today

    Put the Reg round shims in today and there now all around .01 off mean or on Mean

    Put it all back together and it’s exactly the same would not fire up ——- aaahhh !


    But anyway upwards and onwards, so we checked over all the eathing points to no avail

    Then decided to give “Murdo’s
    “ idea with the timing gun

    Connected the new gun to HT cylinder one, nothing and so forth with the other cylinders so we maybe the new gun doesn’t actually work

    Connected to my Bandit on all cylinders and hey presto the gun works !!!

    So it looks like the sparks we had on All cylinder through the plugs sitting on the head are actually weak sparks and not good sparks

    So at this stage it’s looking like the CDI is knackered

    Will try to source a peak voltage tester to confirm the 178v to the secondary coils?

    Any other ideas ?

    Cheers
     
  12. kiffsta

    kiffsta Senior Member

    Messages:
    9,066
    Likes Received:
    6,872
    Trophy Points:
    1,168
    Joined:
    Aug 7, 2010
    Gender:
    Male
    Location:
    Brisbane
    What is the resistance between the 2 plug caps on each coil ? Have you tried snipping a few mm off each plug lead and reattaching the plug cap ?
     
  13. r1rmu13

    r1rmu13 Member

    Messages:
    35
    Likes Received:
    12
    Trophy Points:
    18
    Joined:
    May 13, 2018
    Gender:
    Male
    Location:
    England
    My Bike:
    Honda Cbr250RR MC22
    I will Check tomorrow, good idea about some of the excess off

    I’m currently ordering some bits to make up a peak voltage adaptor, to find out the peak voltage from the pulse gerator and the ignition coils are good

    Cheers
     
  14. my67xr

    my67xr Bike Enthusiast Staff Member Premium Member Contributing Member

    Messages:
    4,313
    Likes Received:
    2,383
    Trophy Points:
    898
    Joined:
    Jun 18, 2016
    Gender:
    Male
    Occupation:
    Panel Beater, Spray Painter, Custom Fabricator
    Location:
    Adelaide, South Australia
    My Bike:
    Yamaha's , 1990 FZR250R 3LN3 , 1986 XT250TS 57R , 1984 IT200L 43G, 1976 IT400C 510
    Check the ohm's reading's through the spark plug cap's too
     
  15. r1rmu13

    r1rmu13 Member

    Messages:
    35
    Likes Received:
    12
    Trophy Points:
    18
    Joined:
    May 13, 2018
    Gender:
    Male
    Location:
    England
    My Bike:
    Honda Cbr250RR MC22
    Still waiting for parts to build a DVA peak voltage adapter so in the mean time thought I would check the stator/ alternator across the 3 pins got 3 ohms on all checks so guess that’s all ok?

    Has anyone checked the regulator? What should you get across which pins?

    It’s a 5 pin tour max type and the 3 yellow wires run to the 3 pins in a line, without the bike running I get a resistance reading from the red and white pin to the 3 yellow pins 1.67 1.7 & 1.7 I presume the green pin is the DC output that can only be checked when the bike is running ?
     
  16. Mike Fulcher

    Mike Fulcher Active Member

    Messages:
    118
    Likes Received:
    38
    Trophy Points:
    53
    Joined:
    Feb 3, 2018
    Gender:
    Male
    Occupation:
    Owner of Mikes Chainsaws & Outdoor Power Ltd
    Location:
    New Plymouth New Zealand
    My Bike:
    85' Yamaha SRX 250, 87' Honda VT250, 86' Suzuki NZ 250, 87' Honda CBX 250, 74' Yamaha AGR100R Racer
    What colour are the center porcelain of the spark plugs? someone has already suggested this may be the simple problem,
    If they are black their is no way in the world the engine will fire up, this condition is called carbon shorting, we come across it often, a quick & easy fix, it often happens when an engine has been sitting around unused with stale fuel & the constant efforts to get the engine to start foul up the plugs.
     
    • Like Like x 1
  17. r1rmu13

    r1rmu13 Member

    Messages:
    35
    Likes Received:
    12
    Trophy Points:
    18
    Joined:
    May 13, 2018
    Gender:
    Male
    Location:
    England
    My Bike:
    Honda Cbr250RR MC22
    There’s no colour as the plugs are new and they are the Iridium equivalent of the OEM, it cannot be the plugs as there is no spark, sorry there is a spark but not a full spark on all cylinders
     
  18. r1rmu13

    r1rmu13 Member

    Messages:
    35
    Likes Received:
    12
    Trophy Points:
    18
    Joined:
    May 13, 2018
    Gender:
    Male
    Location:
    England
    My Bike:
    Honda Cbr250RR MC22
    And on it goes....

    I Have built a DVA or peak voltage adapter that appears to work, now here’s where I’m at, it would appear that I’m not getting the .91+ vdc from the pulse generator to give the cdi the signal to fire...I have checked the resistance at 420 ohms and checked it physically and all appears ok, and no swarf on the magnet

    The question I have; can you have the sensor reading the correct resistance and still be faulty and if so how?

    Cheers
     
  19. maelstrom

    maelstrom LiteTek Staff Member Premium Member 250cc Vendor Contributing Member

    Messages:
    5,102
    Likes Received:
    3,472
    Trophy Points:
    1,148
    Joined:
    Dec 23, 2012
    Gender:
    Male
    Location:
    Thailand
    Home Page:
    My Bike:
    Yamaha FZR400 3TJ1, Honda MC22
    The most likely culprit when ignitions are faulty is the TCI unit. You can buy a Chinese one quite cheaply I believe. Having a spare is a good idea anyway if you plan to keep a 30 year old motorcycle. Same goes for starter motor and rectifier. They just don't last forever. Then when they die you can just swap them out. Pulse triggers rarely fail but it can happen. @my67xr has done some good posts about the Yamaha TCI units and they are all very similar design.
     
    • Like Like x 2
    Last edited: May 30, 2018
  20. my67xr

    my67xr Bike Enthusiast Staff Member Premium Member Contributing Member

    Messages:
    4,313
    Likes Received:
    2,383
    Trophy Points:
    898
    Joined:
    Jun 18, 2016
    Gender:
    Male
    Occupation:
    Panel Beater, Spray Painter, Custom Fabricator
    Location:
    Adelaide, South Australia
    My Bike:
    Yamaha's , 1990 FZR250R 3LN3 , 1986 XT250TS 57R , 1984 IT200L 43G, 1976 IT400C 510
    420 Ohm's should be ok, i have heard of them still running with 480+ Ohm's.
    How much clearance is there from the pick up coil magnet to the flywheel ?
    You want it to have around .25mm to .35mm clearance which is about the thickness of the average business card

    Reg sound's like it's ok, how much does the battery voltage drop when you are cranking it over ?

    With the carby's originally being set with the mixture screw's at 1.5 turn's out, the pilot jet's may have been reamed a bit too much by cleaning them, can you get another new set and try them?
    Thinking it may be a bit rich? Could alway's try starting it without the air filter attached
    Also when you fitted the mixture screw o'ring's did you check the tiny hole's at the bottom of the thread's in the carby base's are open still ?
    If they're blocked or partly blocked it won't start and idle too easily.
    And the mixture screw o'ring's are in the right position, eg mixture screw, spring, washer, o'ring.

    Are you trying to start it with the air filter fitted ?

    And is it a CDI or TCI?
    You might need to check the input voltage and voltage out to the coil's
     
    • Like Like x 1
    Last edited: May 24, 2018

Share This Page