Suzuki TC90, the coolest $30 I've spent in awhile.

Discussion in '2 smokers' started by Bandit240, Nov 4, 2009.

  1. willis 2000

    willis 2000 neo-quixote

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    suzuki used an oil injection system named cci, crankcase injection, on these bikes. it oiled the main bearings directly. it is not a good idea to convert these to premix.
    #41
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  2. jwalters

    jwalters Farkle Proliferator

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    Thanks for the input Willis. I've had other 2 strokes that also suffered from PO's removing the oil injectors. As you say, it's detrimental to the crank and other engine internals. Unfortunately, the PO did the modification, so I'll keep scouring Ebay for an oil tank (or make one). I think I"m just going to tear this engine down this summer fall and start from scratch.

    Of course, now I'm wondering if the cracked oil lines coming off the oil injector aren't causing a crank case leak.... Mmm. I need to get my intake adapter made, so I can use my Motion Pro leakdown test to confirm. Thanks ya'll.



    #42
  3. Red0ktober

    Red0ktober Adventurer

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    Hey guys, nice to see an active thread going on these bikes. When I was a kid I talked my dad into bringing his old TC120 back from his parents shed in Montana where it sat for a couple decades. I played with it for a while, then let it sit in my dad's barn for another decade.

    I wanted to get my dad back into motorcycling, so I figured fixing his old Suzuki would be a good start (turns out I was able to talk him into buying a used DL650 like mine for a trip last year and all went well, anyway...). I found another TC120 on CL and went to buy it as a parts bike for my dad's. I came home with two bikes, the TC120 and a TC90R (guess what I rode to work today).

    I have my bike licensed and insured*, and I sneak around my little town on it, but the lights aren't working. I'm trying to find a headlight housing that will take a standard round sealed beam, without having to hack up anything on the bike. Any ideas on that?

    *insurance on this bike is less than the multi-vehicle discount it gives me, so it's effectively lowering my V-Strom's insurance. :D
    #43
  4. BigVicProton

    BigVicProton n00b

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    What do you mean by sucks air on induction? I have a '74 TC100 and it runs great, but only with the side plate covering the carbs off. put it on and it will bog and die when you give it throttle. Carb is clean and gas is clean...so maybe its this induction?

    #44
  5. Red0ktober

    Red0ktober Adventurer

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    My tiddler quit running! No spark! I tried a known good coil off my dad's TC120 which hasn't been run in a decade, but I tested it for spark before I pulled it. Looks like the HT lead on the TC90 coil was damaged, but it's been working this long.

    I have not tested the ignition switch yet, simplest things first, I know...

    Other than that, I don't know how to troubleshoot these old ignition systems. Any tips?
    #45
  6. twinsig

    twinsig Been here awhile

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    wow, was my first bike @ 13, same color!
    #46
  7. mungus

    mungus Been here awhile

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    Actually per the instructions for fitting the factory "scrambler" kit you DO convert them to run on pre-mix. I had a TS90 (same motor as the TC90) scrambler back in the 1970's (yeah I know, old bastard), and I did just that. Ran fine at 30:1, no problems at all... And why wouldn't it. CCI was mostly a marketing tool. Trying to make cheap 2 strokes as easy to live with as a 4 stroke, by not having to make pre-mix at the gas station.
    #47
  8. slideways

    slideways España

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    You still have to run oil to the crank via the small oil bottle that comes with the hop up kit. Other wise the crank would eventually give up.
    That is the reason for the small bottle beside the kick start.
    IMG_2186.JPG
    #48
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  9. mungus

    mungus Been here awhile

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    Well true. But the point is there is nothing inadvisable about running pre-mix. I did it for ages, one day I noticed the little bottle had run empty but it was still going strong. I guess 30:1 would delay the implosion a fair old while...
    Page instructing the owner to do so, from the Scrambler kit instructions, is attached for interest. I like how they are specific about which bearing might fail!

    Attached Files:

    #49
  10. LandsVW

    LandsVW Been here awhile

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    757
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    Tri City, Oregon
    Just got one of these!
    4EC794BE-1820-4F43-A0FD-CFB652684A62.jpeg

    Have a second one, which a long time ago I Put an xr100 Engine into. This one I think I will keep stock.


    3BAD9C10-6199-41C9-8B1E-197E7AE73A3D.jpeg


    There’s my XR’d one, given to me for free. After laying in a field for 20 years on its side, the Engine was toast. It was evidently spray painted by a kid. And had no fenders... so I improvised. I had an XR100 engine handy... I’m really hoping I saved the original carburetor and etc, because the green one doesn’t have the carb. The other one is at my moms house in Alaska, so will investigate my bike part hoarding shelf this summer when I go visit.
    #50
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  11. LandsVW

    LandsVW Been here awhile

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    I'm working on the TC90. The left side was completely disassembled and in a box. There seems to be at least a stainless type washer that I can't identify where it goes. Does anyone have a parts diagram of this bike engine? Online it seems rather sparse...
    #51
  12. LandsVW

    LandsVW Been here awhile

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    I think I figured it out. Extra parts mingled with Tc90 parts...
    #52
  13. Carmackle

    Carmackle Been here awhile Supporter

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    Check alpha-sports.com for parts diagrams for that TC.
    I have a '71 model and alot of parts are still available.
    Good luck.
    #53
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  14. beeker12

    beeker12 Been here awhile

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    Pretty Rad little bike. I have more fun on that bike than my Beta Xtrainer. Surprises the hell out of the guys with 185's 754BD841-07DB-48FE-B480-EF2D52132AFB-X2.jpg
    #54
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  15. LandsVW

    LandsVW Been here awhile

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    Got a lot done on it today! Piston and cylinder reinstalled, and most of the left side reassembled (side cover was damaged and everything in a box -eBay special got me a side cover).

    Yes, I really like these bikes. I had 2 TC 125’s as a teenager, and then still have my Frankenbike TC90 with the XR100 Engine. Super easy to ride. I’d say it’s biggest downfall is the bouncy rear suspension.

    I may post a picture of the washer, as I just can’t find it on any pictures and it looks kind of specialty. But there were other parts obviously in with the TC parts so could just be a random washer.
    #55
  16. CJBDRdude

    CJBDRdude Ridin'offroadCJ

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    My first full size bike too, 72' TC90J Blazer . Cool bike with the dual range tranny. That thing would climb up anything it could get traction on.
    #56
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  17. LandsVW

    LandsVW Been here awhile

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    +1 on the dual range tranny! They are so light, and look good too!
    #57
  18. LandsVW

    LandsVW Been here awhile

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    Got the left side completely together, except for clutch cable which I’m almost positive I have up in Alaska, as well as the carburetor. So, bike is all back together except for carb, a cable, and a few adjustments. Parked in back of garage and will await summer and my trip up there!
    #58
  19. scmopar

    scmopar Been here awhile

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    I have one of these in the shed now I was told it was running when parked that was 1986ish. it needs a new home.
    #59
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  20. LandsVW

    LandsVW Been here awhile

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    Wish I was closer...
    #60