77 yam rd400 your thoughts?

Discussion in 'Old's Cool' started by metlcutr55, Jan 12, 2007.

  1. metlcutr55

    metlcutr55 LongGoneDaddy

    Joined:
    Dec 12, 2004
    Oddometer:
    901
    Location:
    s w NH
    looking for opinions...i have a line on a bike i really like the looks of....1977 yam rd400 c with chrome chambers...dont know why i want it but i really do...got rid of an h2 few years ago, lot more fun to look at than ride, i should know better. its at a 2nd hand dealer, says 3700 mi, fresh top end (why i dunno guessing it sat maybe), pics look real good, stock except for the pipes. havent seen it in person but in headed soon. $2k. im all ears...:ear
    #1
  2. El Hombre

    El Hombre Banned

    Joined:
    Jul 19, 2006
    Oddometer:
    1,536
    Location:
    Alta Coma, California
    Crank seals were always suspect on those. You get to split the cases. Usually, you find about it when it seizes. Good reason why it's got a new top end.

    Then get the Kmart coils, or equivalent, to fix the plug fouling. Don't know how to do that? Dig up the 32 year old Cycle Magazine issue about it.

    Yamaha's suck, big time. Go get another Kaw.

    Blue turds.

    Rant off.
    #2
  3. metlcutr55

    metlcutr55 LongGoneDaddy

    Joined:
    Dec 12, 2004
    Oddometer:
    901
    Location:
    s w NH
    no more kaw triples for me...always outta sync, wont stop or go around a corner....i wonder if fresh top end just means rings and pistons...i know its one of the least collectible but she keeps calling my name...bringg..ding..ding..ding...
    [​IMG]
    #3
  4. no5s

    no5s Terror at 2 mph

    Joined:
    Oct 24, 2004
    Oddometer:
    358
    Location:
    Oceanside
    One of my favorite bikes. Way aread of it's time. Brakes and suspension good. Best wheelie machine ever. Self cancelling turn signals. Buy it, fix it, ride it.
    #4
  5. dan-c

    dan-c Back

    Joined:
    Aug 19, 2005
    Oddometer:
    13,787
    Location:
    SATX
    Crank seals. Usually you can tell they're leaking if it somkes like hell. They suck the transmission oil intot he rank case. IMO, I don't think the old Yamahas crank seals degrade as bad as Suzukis or Kawasakis.
    Fresh top end. If the guy took care of the bike, it may have only needed rings or he could have had it bored and fresh pistons and rings. Big deal, that's easy stuff on a two-stroke :deal . The pulg fouling on the RD's was pretty much cleared up after the - model. Get iridium pulgs and throw in there. Only use Yamalube S2. Shouldn't be an issue.
    That bike looks nice, but 2 large is a premium for the bike.
    #5
  6. farmer fred

    farmer fred Banned

    Joined:
    Aug 21, 2006
    Oddometer:
    1,488
    I'd take an RD over a Kawasaki triple any day, if you are going to ride it. I am having a crank rebuilt for my 79 Daytona as I type this.

    The trouble with chambers is who jetted it? Stock is usually best.

    The price seems a bit high. Look around at http://www.usa2strokers.com/forum/default.asp for advice/ideas/sources.
    #6
  7. Motomech

    Motomech Adventurer in Latin Amer.

    Joined:
    Dec 29, 2005
    Oddometer:
    337
    Location:
    Playas del Cocos, Costa Rica
    I owned, raced and worked on RD's for ten years, so I will try and clear up some myths here.

    First off, unless it was stored in a enviormently controled storage area, the crank seals will have likely dried out. It won't be a problem at first, but, as mentioned, the trannie oil will likely start to be pulled into the crankcase, resulting in copious smoking. If it was stored in a humid place, the brg.s may have become rust pitted and the same thing will happen(the brg.s will develop play and hog out the seals, which will in turn start to leak). If I had to guess, I would say that these prob.s would start to develop around 10,000 miles for the RD we are talking about. Yes, the cases need to be split to replace the main brg.s and seals, but the crank would not have to be rebuilt, as I think the center brg. and labrynth seal would be ok and the crank would still be in true. Stock and mild RDs avg. 20K on main brg.s and 40K on cranks. Cranks for twins, unlike tripples, do not need a jig to rebuild, so it's not hard to find someone to do that. Crank brg. play is ck.ed by feeling for movement at the rotor. If any is felt, it's time.

    Unlike the 350's(which I perfered), the 400's do not respond well to partial mod.s. They perfer to be stock or wild. In the case of the RD in question, I would leave the pipes on and retain the stock airbox(important). That way, all it would need is to go up one or two sizes on the main jets, if that had not already been done.. I would add Boost Bottles and leave it at that.

    It's totally false that RD's need the big, silly looking aftermarket coils to keep from fouling spark plugs. What they do need is;
    1]to be mechanicaly sound
    2]have the Autolube Injection pump properly adjusted(this is done removing shims on the plunger until the proper amont of stroke is attained, I would take it down to just a few thousands of an inch).
    3]Feed a quality two stroke oil, I perfered Bel-ray SI-7.
    4]To have quality contact breaker asm.'s intalled and properly timed. By quality points sets, I mean Yamaha, if still available and ND if they are not. Timing is set with a dial guage and a spark plug boss adapter. Breakers need to be adjusted every 10K and replaced at 20K. Use only the stock NGK plugs, B8HS, i think.

    The DS7, R5 and RD line of bikes were the first good handling and stearing bikes to come out of Japan, way better than the Kawasaki tripples. The 350's are akind to riding a rail as far as comfort went and Yamaha softened the 400's to the point that the '78 400 was like riding a beach ball. It's easy enough to cut down the seat and if you get this bike, you will want to get aftermarket shocks.
    As with all bikes that have sat, you want to take a good look inside the fuel tank. If it's not clean and shinny, you will be in for lot's of extra work(assuming the carb.s will be totally gunked-up as well0.

    Yes, RD's are maintainence intensive, but they are rewarding bikes, even today.
    #7
  8. Mattbastard

    Mattbastard Lazy ass

    Joined:
    Mar 30, 2005
    Oddometer:
    2,233
    Location:
    Sheboygan
    I like my car coils. :cry


    [​IMG]
    #8
  9. Motomech

    Motomech Adventurer in Latin Amer.

    Joined:
    Dec 29, 2005
    Oddometer:
    337
    Location:
    Playas del Cocos, Costa Rica
    Yeah, weee bad!
    Looks like a nice 350. I was sooo queer for RD350's in the late '70's. Did every trick in the book and then some.
    Is that a trails tire on the frt.?
    #9
  10. Mattbastard

    Mattbastard Lazy ass

    Joined:
    Mar 30, 2005
    Oddometer:
    2,233
    Location:
    Sheboygan
    Nah, I forget what they are, but I got em from HVCcycle with a bunch of other shit for my smoker.

    That bike's a hoot. It flat out rips twisties like nothin' else I've owned, including an R1. I dont know why this is, but it's just more fun. I've always heard that it's more fun to ride a slow bike fast than a fast bike fast. Not that my RD350 is slow, but topping out at only 110 makes it slow by todays comparison. It's definetly a labor of love too. I bought it for the completely overpriced value of $600, and put a bit more than that back into it, not to mention over about 200 hours of labor total. Complete engine tear down, new gaskets/seals/cables/paint/etc.. Then there was the learning curve for tuning :wink: This definetly gave me a new perspective on tuning carbs.

    The bike has definetly grown on me. I may never sell it, not because i'd never get out of it what I've put in, but because of it's character. You dont hear piped smokers on the road anymore. One time last summer I was pulling up to a job (electrician) and got to BS'in with the homeowner for the better part of an hour over the damn thing. He said he hadn't heard that sound in over 20 years. That's what I like about it, it's more original than a harley now a days.
    #10
  11. markjenn

    markjenn Long timer

    Joined:
    Nov 9, 2003
    Oddometer:
    10,506
    Location:
    Swellvue, WA
    Looks great for cooling the coils. The engine doesn't fare so well.

    - Mark
    #11
  12. SteveBroskey

    SteveBroskey Teach me this knowledge

    Joined:
    May 30, 2006
    Oddometer:
    541
    Location:
    Rochester, NY
    Buddy's told me to keep an eye out for an RD 400 for him since I bought my DT last year. I don't know a thing about them but he told me he'd come from TX to NY to pick it up if I could find one - so he's smitten...
    #12