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

Help Help Wanted - Yamaha SR400

Discussion in 'Maintenance' started by Murdo, Nov 21, 2018.

  1. Murdo

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

    Messages:
    5,103
    Likes Received:
    4,008
    Trophy Points:
    1,148
    Joined:
    May 4, 2013
    Gender:
    Male
    Occupation:
    Retired
    Location:
    Tamworth, NSW
    My Bike:
    Maico 250, Royal Enfield 250, CF 250 V5 and 650TK, XL250, CBR250, ZZR250 plus a few others.
    Trying to help my mate out with his SR400.
    xxx 001.jpg
    The ignition has died and by testing the coil, pick ups and relays they all show correct readings. This leads me to believe that the TCI box is faulty but am having trouble finding a reasonably priced replacement. Yamaha want $700 for a new one. Second hand from Japan are around $350+, so am asking the brains trust 'do you have any suggestions that won't cost more than the bike is worth'?
    The bike is 1992 model 3GW with a Denso 070000-2540 unit.
    Toys 011.jpg
    Thanks.
     
  2. my67xr

    my67xr Bike Enthusiast Staff Member Premium Member Contributing Member

    Messages:
    3,606
    Likes Received:
    2,066
    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
    Does it look like it can come apart easy, or is it potted into the housing with epoxy?
     
  3. Murdo

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

    Messages:
    5,103
    Likes Received:
    4,008
    Trophy Points:
    1,148
    Joined:
    May 4, 2013
    Gender:
    Male
    Occupation:
    Retired
    Location:
    Tamworth, NSW
    My Bike:
    Maico 250, Royal Enfield 250, CF 250 V5 and 650TK, XL250, CBR250, ZZR250 plus a few others.
    I had a bit of a dig on the end where the wires come out, it looks like sikaflex type stuff all the way through. Will cut the back off tomorrow with a dremel and see what is inside.
    Really looking for a cheap replacement to get him back on the road.
     
  4. my67xr

    my67xr Bike Enthusiast Staff Member Premium Member Contributing Member

    Messages:
    3,606
    Likes Received:
    2,066
    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
    If you cant find a replacement, Small coil rewind's in Geelong could probably repair it for you, not sure what they charge now tough.


    Here's a video showing how to clean up the board with Acetone,
    it could be the same problem as this circuit board, a lot of dry soldered joint's and some bad capacitor's

     
  5. kiffsta

    kiffsta Administrator Staff Member Dirty Wheel Club Contributing Member

    Messages:
    8,107
    Likes Received:
    5,931
    Trophy Points:
    1,168
    Joined:
    Aug 7, 2010
    Gender:
    Male
    Location:
    Brisbane
    Home Page:
    My Bike:
    90 CBR250RR ,Suzuki T500, 2005 GSF1200 Bandit and a 1972 t250j
    If that fails , maybe try findapart.com.au , or join the sr400 Facebook group and ask if someone has one.
     
  6. Murdo

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

    Messages:
    5,103
    Likes Received:
    4,008
    Trophy Points:
    1,148
    Joined:
    May 4, 2013
    Gender:
    Male
    Occupation:
    Retired
    Location:
    Tamworth, NSW
    My Bike:
    Maico 250, Royal Enfield 250, CF 250 V5 and 650TK, XL250, CBR250, ZZR250 plus a few others.
    Thanks for the replies. Bike was going one day and would not start the next. Been off the road a couple of months now and he is getting ichy to ride again.
    Have a request on findapart.
    Going to cut open the box today.
    I wonder how hard it would be to fit up something like this? For the price it may be worth a gamble as they are both single cylinders.
    https://www.aliexpress.com/item/12V...lgo_pvid=519a90c1-5a28-4ae0-9234-62323371eecb
     
    Last edited: Nov 22, 2018
  7. my67xr

    my67xr Bike Enthusiast Staff Member Premium Member Contributing Member

    Messages:
    3,606
    Likes Received:
    2,066
    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
    Those AC 'Racing'cdi's can be a bit hit and miss, some were set up for use on 2 stroke bike's so had a bit too much advance built in.
    Some of them were cheaply made and fail out the box or failed within a month
    A lot of the pit bike lad's have tried them out but end up going back to a standard type cdi, they are early CRF50 /KLX110 based

    The first one listed below you would have within a week from Blygo, sometime's will receive them in a couple of days



    There is also a DC version of the Racing cdi, the wiring socket's look pretty close but they wont work with an AC Stator



    https://www.ebay.com.au/itm/Perform...=item417d14dd07:g:T24AAOxyGwNTCBP9:rk:34:pf:0

    hp_200cc_250cc_coil_cdi_unit_01.jpg

    https://www.ebay.com.au/itm/Ignitio...=item1ee94bdff8:g:S5YAAOSwxKNbh8Xz:rk:88:pf:0

    tm315_td019.jpg

    Here's a wiring diagram.

    6pinout.jpg
     
    • Like Like x 1
  8. maelstrom

    maelstrom LiteTek Staff Member Premium Member 250cc Vendor Contributing Member

    Messages:
    3,417
    Likes Received:
    2,344
    Trophy Points:
    923
    Joined:
    Dec 23, 2012
    Gender:
    Male
    Location:
    Thailand
    Home Page:
    My Bike:
    Yamaha FZR400 3TJ1, Honda MC22
    Ignitech make for single cylinder.
     
  9. ruckusman

    ruckusman Well-Known Member Premium Member Dirty Wheel Club

    Messages:
    1,652
    Likes Received:
    799
    Trophy Points:
    693
    Joined:
    Oct 1, 2013
    Gender:
    Male
    Location:
    Narrabeen, NSW Australia
    My Bike:
    Yamaha FZR250 3LN1
    See if giving a gentle heat soak on the out shell with a heat gun set to not much more than hairdryer heat makes it easier to extract the innards before

    Once open we can probably provide hints on the repair replacement of relevant parts - I assume you can solder :prankster::prankster::prankster:
     
    • Like Like x 1
  10. Murdo

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

    Messages:
    5,103
    Likes Received:
    4,008
    Trophy Points:
    1,148
    Joined:
    May 4, 2013
    Gender:
    Male
    Occupation:
    Retired
    Location:
    Tamworth, NSW
    My Bike:
    Maico 250, Royal Enfield 250, CF 250 V5 and 650TK, XL250, CBR250, ZZR250 plus a few others.
    Ah yep. :p
    Thanks 67xr. Will keep that as a last resort.
    After soaking in Acetone all day I have managed to get about half of the rubbery stuff off. Will continue soaking overnight to hopefully get it all off in morning.
    More toys 011.jpg
     
  11. ruckusman

    ruckusman Well-Known Member Premium Member Dirty Wheel Club

    Messages:
    1,652
    Likes Received:
    799
    Trophy Points:
    693
    Joined:
    Oct 1, 2013
    Gender:
    Male
    Location:
    Narrabeen, NSW Australia
    My Bike:
    Yamaha FZR250 3LN1
    I came across mention of silicone remover when reading about roofing silicone recently - it might speed thing up, especially in the little pieces between the electronic components

    http://www.selleys.com.au/sealants/silicone-and-other-sealants/roof-gutter/#information

    MSDS - https://go.lupinsys.com/duluxgroup/...arch_api/SELLEYS_SILICONE_REMOVER-AUS_SDS.pdf

    From the MSDS
    Naptha is camping stove fuel, not sure about hydrotreated heavy - Naptha is a non polar solvent, safe for cleaning things such as archival film, won't eat plastics

    This looks more like the active ingredient
    Benzenesulfonic acid, C10-C16 alkyl derivatives

    You could test it on a piece of dead electronics and check it doesn't eat exposed copper traces though they should be all covered with lead solder anyway
     
    • Thanks! Thanks! x 1
  12. ShaneP

    ShaneP Well-Known Member Premium Member Contributing Member

    Messages:
    1,771
    Likes Received:
    714
    Trophy Points:
    623
    Joined:
    May 12, 2014
    Gender:
    Male
    Location:
    Yeppoon
    My Bike:
    Yamaha FZR250 speed bike, Yamaha YZ/WR250F, Kawasaki ZX2R, Honda VTR250, DR350 (x 3.5), a couple of prototypes and whatever else.
    A bit late seeing this. I did a stator and pick up coil test (resistance in circuit) and found it to be in spec. But fortunately my mechanic made me double check by testing for leak (see if it leaks to earth) and that it produces pulses. I'm probably being rude suggesting this to a man of experience like Murdo, but I'd stay out of the igniter as long as possible. I see there are a for inputs, would one or 2 be kill switch, and another be kickstand? Possibly a clutch, too? Checked those circuits, too?
     
  13. Murdo

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

    Messages:
    5,103
    Likes Received:
    4,008
    Trophy Points:
    1,148
    Joined:
    May 4, 2013
    Gender:
    Male
    Occupation:
    Retired
    Location:
    Tamworth, NSW
    My Bike:
    Maico 250, Royal Enfield 250, CF 250 V5 and 650TK, XL250, CBR250, ZZR250 plus a few others.
    Yes I have, which is why I'm pulling the cdi box apart.
     
  14. my67xr

    my67xr Bike Enthusiast Staff Member Premium Member Contributing Member

    Messages:
    3,606
    Likes Received:
    2,066
    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
    Another thing to watch out for with solvent's is removing marking's off the transistor's, and capacitor's etc
    Main thing is to get all the soldered joint's pretty clean so you can check for cracked joint's etc, reflow anything suss and try it out
     
    • Informative Informative x 1
  15. Murdo

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

    Messages:
    5,103
    Likes Received:
    4,008
    Trophy Points:
    1,148
    Joined:
    May 4, 2013
    Gender:
    Male
    Occupation:
    Retired
    Location:
    Tamworth, NSW
    My Bike:
    Maico 250, Royal Enfield 250, CF 250 V5 and 650TK, XL250, CBR250, ZZR250 plus a few others.
    Have the board cleaned and checked all soldered joints in strong light with my glasses on and cannot see any problems. Have checked all the wires to board with meter and all good too.
    glen innes 005.jpg glen innes 007.jpg
     
    • Like Like x 2
  16. ruckusman

    ruckusman Well-Known Member Premium Member Dirty Wheel Club

    Messages:
    1,652
    Likes Received:
    799
    Trophy Points:
    693
    Joined:
    Oct 1, 2013
    Gender:
    Male
    Location:
    Narrabeen, NSW Australia
    My Bike:
    Yamaha FZR250 3LN1
    For no spark I am going to recommend that you read out the chip ID's of those two large transistor sitting upright

    Will likely be one alpa followed by 4 numerals starting with A, B, C or D - if my guess is corect
     
  17. my67xr

    my67xr Bike Enthusiast Staff Member Premium Member Contributing Member

    Messages:
    3,606
    Likes Received:
    2,066
    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
    To test it out, plug it in to the bike and make sure nothing is touching any metal, warm the soldered side of the circuit board with a heat gun, now try and start the bike and see what happen's.
    If it fire's and start's , i would just resolder each joint that you can see and try it out on the bike again
    If it work's then you can reassemble the board into the box and refit it

    If it doesn't start or fire then it might be worth replacing the 2x transistor's, i might have a couple spare if you can give me the part number's or post a picture.

    I'm guessing there's no burnt track's either ?
     
    • Like Like x 1
  18. Murdo

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

    Messages:
    5,103
    Likes Received:
    4,008
    Trophy Points:
    1,148
    Joined:
    May 4, 2013
    Gender:
    Male
    Occupation:
    Retired
    Location:
    Tamworth, NSW
    My Bike:
    Maico 250, Royal Enfield 250, CF 250 V5 and 650TK, XL250, CBR250, ZZR250 plus a few others.
    To end this saga, my mate got an electronics 'expert' to rebuild the box for him and it now fires up first kick. :party:
     
    • Winner Winner x 4
    • Like Like x 2

Share This Page