Page 5 of 34 FirstFirst ... 3456715 ... LastLast
Results 61 to 75 of 501

Thread: Old multi-cylinder bikes of the 50s to later on. Japanese, British, Euro, etc

  1. #61
    Join Date
    20th January 2010 - 14:41
    Bike
    husaberg
    Location
    The Wild Wild West
    Posts
    11,823
    Quote Originally Posted by T.W.R View Post
    Um it is actually a square 4

    The write-up from when it was produced states:

    250cc 4 cylinder
    using parallel crankshafts, two diagonally opposed cylinders fire together
    produces 52hp @ 12500rpm
    22mm bore carbs feeding disc intake valves
    multi plate dry clutch

    and it was raced in 1964-65 albeit not very successfully with being notoriously difficult to tune & also heavy

    Yamaha made a 250 V4 8spd a bit later at the end of 65 revealed it at Monza, produced 60hp. And at the IOM was clocked at 150mph.
    It was essentially two of the 125 engines grafted together on a common crank.


    Nah look at the pics it is a V formation. it is therefor a V.

    Same as a YZR500, RGV500 and Cagiva etc the only common 4 cylinder single crank engines were swissauto and Honda plus Patton.
    http://www.d-mengineering.co.uk/news...category_id=14
    Quote Originally Posted by Katman View Post
    I reminder distinctly .




    Kinky is using a feather. Perverted is using the whole chicken

  2. #62
    Join Date
    19th October 2005 - 20:32
    Bike
    M109R, GS1200ss, RMX450Z, ZX-12R
    Location
    Near a river
    Posts
    4,308
    Quote Originally Posted by husaberg View Post
    Nah look at the pics it is a V formation. it is therefor a V.
    explain the rotary valve intakes then if it was a V format how come there's two of them and where's the crank

    and lol look and learn

    Yamaha 250 V4 1966

  3. #63
    Join Date
    25th March 2004 - 17:22
    Bike
    RZ496/Street 765RS/GasGas/ etc etc
    Location
    Wellington. . ok the hutt
    Posts
    20,500
    Blog Entries
    2
    Boy this is getting tedious fast.

    Lets just agree to disagree. Even the Japs weren't that pedantic.
    Don't you look at my accountant.
    He's the only one I've got.

  4. #64
    Join Date
    16th September 2004 - 16:48
    Bike
    PopTart Katoona
    Location
    CT, USA
    Posts
    6,542
    Blog Entries
    1
    Yeah that design has always been a problem. Technically it's neither as a V would have an angled block and the pistons would move at the same angle away from each other and if it were a true square it would have 2 cranks with conrods attached meeting a central geared drive (i.e. conrods would be horizontal and parallel).

    So V conrods in a square block is neither.
    Reactor Online. Sensors Online. Weapons Online. All Systems Nominal.

  5. #65
    Join Date
    25th March 2004 - 17:22
    Bike
    RZ496/Street 765RS/GasGas/ etc etc
    Location
    Wellington. . ok the hutt
    Posts
    20,500
    Blog Entries
    2
    I don't think the design is a problem at all. While they were legal people raced them, other people tried to make them faster, where's the problem? (rivet counters arguing on the internet 40+ years later aside, as indeed they should be).
    Don't you look at my accountant.
    He's the only one I've got.

  6. #66
    Join Date
    16th September 2004 - 16:48
    Bike
    PopTart Katoona
    Location
    CT, USA
    Posts
    6,542
    Blog Entries
    1
    Quote Originally Posted by F5 Dave View Post
    I don't think the design is a problem at all. While they were legal people raced them, other people tried to make them faster, where's the problem? (rivet counters arguing on the internet 40+ years later aside, as indeed they should be).
    Ask Ariel
    Reactor Online. Sensors Online. Weapons Online. All Systems Nominal.

  7. #67
    Join Date
    25th October 2002 - 12:00
    Bike
    Old Blue, Little blue
    Location
    31.29.57.11, 116.22.22.22
    Posts
    4,859
    1968 Suzuki RP68 50cc triple - 19 hp @ 19,000rpm, 16 speed gearbox - only one made - unfortunately, never raced as they changed the rules.......



    engine


    cranks




    so - is it a V3, or with 3 seperate cranks, a W3?
    “- He felt that his whole life was some kind of dream and he sometimes wondered whose it was and whether they were enjoying it.”

  8. #68
    Join Date
    25th March 2004 - 17:22
    Bike
    RZ496/Street 765RS/GasGas/ etc etc
    Location
    Wellington. . ok the hutt
    Posts
    20,500
    Blog Entries
    2
    Its just fukn cool, lets leave it at that. And Ironically the only bike in this thread eligible from a capacity point of view as a bucket. however if it was never raced, does that make it non-competition?

    Argh, now you have me doing it Stoppit.
    Don't you look at my accountant.
    He's the only one I've got.

  9. #69
    Join Date
    20th January 2010 - 14:41
    Bike
    husaberg
    Location
    The Wild Wild West
    Posts
    11,823
    Quote Originally Posted by F5 Dave View Post
    Its just fukn cool, lets leave it at that. And Ironically the only bike in this thread eligible from a capacity point of view as a bucket. however if it was never raced, does that make it non-competition?

    Argh, now you have me doing it Stoppit.
    I rarely agree with Dave, but yes lets stop the arguing, who gives a Rats buttocks.

    Other than i posted the Rc "what ever" 125/5 somewhere plus i think a few CR93 and probably a CR110 or two but they all are completion bikes.
    The 50/3 is cool of course i have a write up on Bazza's Twin he re restored i will post when i can be arsed.

    RE the YAM V4 A mad (Dutchy i think Blower) or something has made a reproduction one reasonably recently.

    Anyway if i was going to be pedantic the Yam example posted as an example of a V4 above..... er has two cranks.LOL
    Oh the irony

    Quote Originally Posted by husaberg View Post
    Yamaha also had some fiendishly complex auto lube systems on the 60's multi GP bikes.



    Honda's approach on the MB was ingenious in its simplicity.

    Yes looking at the engine diagram for the V4 it does look like it had pressure feed big ends but it reved to over 17000......


    I think the wolf/stinger may have pressure feed the big ends as well?
    But i are not yet 40 so not sure.
    IF you click on the arrow the Classic racer write up is in the original post....
    Quote Originally Posted by husaberg View Post
    120 or so pages back Frits and I (Big Pics are Frits's) posted some pics of the V4 Yam 2 stroke 125 gp bike. (RA31 and RA31A)





    here is it's big brother It is well worth a read, even if i do say so myself.

    3rd fastest bike in the speedtrap at 1967 the IOM. carrying 15kg of Lead ballast (The two faster bikes were Ago on a 500cc MV and Hailwood on the 500cc Honda "Camel" not bad for a 250 aye.
    plus the speed compared to Spencer's 250.)
    Quote Originally Posted by Katman View Post
    I reminder distinctly .




    Kinky is using a feather. Perverted is using the whole chicken

  10. #70
    Join Date
    13th June 2010 - 17:47
    Bike
    Exercycle
    Location
    Out in the cold
    Posts
    5,626
    Quote Originally Posted by SPman View Post
    1968 Suzuki RP68 50cc triple - 19 hp @ 19,000rpm, 16 speed gearbox - only one made - unfortunately, never raced as they changed the rules.......

    so - is it a V3, or with 3 seperate cranks, a W3?
    it's just a bloody triple...and it may not have started an FIM GP but I'm pretty sure Suzuki sent it to the US where Ron Grant raced it - probably as a promotional thing. Source - old Cycle mags quoting Ron riding the 50 triple which went off song when a cloud crossed the sun...

    Just to wind up the pedants...a flat twin ala BMW is a 180 degree Vee, and a parallel twin ala Triumph, BSA is a 360 degree Vee...they are of course the extremes of the type.

    Carry on...

  11. #71
    Join Date
    20th January 2010 - 14:41
    Bike
    husaberg
    Location
    The Wild Wild West
    Posts
    11,823
    Quote Originally Posted by Grumph View Post
    it's just a bloody triple...and it may not have started an FIM GP but I'm pretty sure Suzuki sent it to the US where Ron Grant raced it - probably as a promotional thing. Source - old Cycle mags quoting Ron riding the 50 triple which went off song when a cloud crossed the sun...

    Just to wind up the pedants...a flat twin ala BMW is a 180 degree Vee, and a parallel twin ala Triumph, BSA is a 360 degree Vee...they are of course the extremes of the type.

    Carry on...
    or "A square 4 is a Zero degree V4 then"
    There is a Write up scanned out of a Classic Racer i think two tempi or ChrisC posted on the ESE thread.

    Quote Originally Posted by chrisc View Post
    I saw this in the August 2012 issue of Classic Bikes, page 65 if anyone wants to check it out for a similar read

    OH it was just the twin i think
    Quote Originally Posted by Katman View Post
    I reminder distinctly .




    Kinky is using a feather. Perverted is using the whole chicken

  12. #72
    Join Date
    1st February 2004 - 11:00
    Bike
    MG V11 Nero Corsa LeMans
    Location
    out west a chch
    Posts
    9,469
    Quote Originally Posted by husaberg View Post
    Nah look at the pics it is a V formation. it is therefor a V.
    Ohhh mate, no no no... that like ducatis bevels is a L format a L4 in this case
    cheers DD
    (Definately Dodgy)



  13. #73
    Join Date
    31st July 2005 - 11:15
    Bike
    a shed full of crazy shit
    Location
    Palmerston North
    Posts
    2,201
    Yummm

    http://page11.auctions.yahoo.co.jp/j...ion/n119056986


    RGB500. Someone please buy it and bring it to NZ...

    only 3,130,000 yen (31k NZD)

    shocking translation:

    I think as not feel missing parts you see on RGB500-Ⅱ type cranking OK.
    Radiator water, brake OIL etc. are not included.
    It is the person who would like to be able to examine it check the current car is basically a condition delivery no claim in any case.






    and while I'm at it...
    one of my fav youtube clips (outside on the GPR crash test).
    Hugh Anderson gets quite a mention.


  14. #74
    Join Date
    20th January 2010 - 14:41
    Bike
    husaberg
    Location
    The Wild Wild West
    Posts
    11,823

    Mt125r

    I Swiped part or all of this
    Quote Originally Posted by bucketracer View Post
    [b].

    Attachment 258303

    in 1978 the honda over the counter 125 factory racer made 25 and then later 28 hp and was the for runner of the rs125.

    Attachment 258304

    Attachment 258305
    and the honda also had a bridged exhaust port, while teezee has to contend with the limitations of a single exhaust port.

    Info scraped of the net about the honda mt125r

    - bike was produced and modified by honda rsc (racing service corp., the forerunner to hrc)
    - three versions were made mki, mkii, mkiii from 1977-78
    - approx 200 imported into us each year.
    - bike dry weight 165lbs.
    - engine configuration is factory modified version of the 1977 elsinore motocross based engine
    - narrow power band with road race porting - "on the pipe" from 9,500 - 13,000rpm
    - 6-speed with "ultra close" road race internal gearbox ratios - shifter mounting rearwards
    - road race specification porting and factory 34mm carb - 25.5hp @ 12,5000rpm for mki, mkii
    - mki had a mechanical activated disk brake from a cb200
    - mkii & mkiii had upgraded front hydraulic disk brake
    - final mkiii in '78 had additional porting, pipe changes for 28hp peak
    - rsc offered a special factory water cooling kits in 1978, including pipe, cylinder., head, radiator, mounts, and special side cover with external water pump.
    - water cool kit avoided the heat-induced power loss form running at 13,500 rpm in a long race.
    - top speed (with a light rider!) approx 115 mph.
    - i have achieved 108mph at daytona with 185lb rider.

    As with any 125 cc roadracer, it was best suited for smaller riders. After bump starting the engine a good start required patience and finesse. To characterize the personality of the 125 cc two-stroke look at the rsc factory tachometer. It did not move or display engine rpm until 5,000 rpm and registered up to 14,000 rpm. With the tall gearing needed for top speed performance it would not pull its own weight until the tachometer was showing at least 9,000 rpm. The engine was in its peak powerband or, "on the pipe" from just below 10,000 rpm and went out of the powerband a little past 11,000 (depending on jetting and modifications).

    To achieve a good start the rider needed to hold the throttle wide open and begin feathering the clutch as fast as possible while keeping the rpm between 10,000 and 11,000 rpm. If the tachometer dropped below 10,000 rpms the rider needed to pull the clutch in, rev the motor and begin the process again. If the clutch was engaged too quickly the engine could "bog" or even stall while the rest of the starting field rode away. Even with the lightest of riders, the mt125r required slipping the clutch for 40 or more feet. The rewards for a successful launch were full throttle with quick shifts (approximately every 1,000 rpm) up through the six gears. At the end of sixth gear the hard-working 123 cc engine would be pulling along a straight stretch between 110 and 120 mph.

    The last hondas made 28 hp and had a 2.5k power band,
    Attached Thumbnails Attached Thumbnails Click image for larger version. 

Name:	MT125R.JPG 
Views:	53 
Size:	304.8 KB 
ID:	287913   Click image for larger version. 

Name:	MT125R 2.JPG 
Views:	52 
Size:	343.8 KB 
ID:	287914   Click image for larger version. 

Name:	MT125R 3.JPG 
Views:	44 
Size:	288.0 KB 
ID:	287915   Click image for larger version. 

Name:	Mt125r.JPG 
Views:	40 
Size:	315.2 KB 
ID:	287916   Click image for larger version. 

Name:	MT125rb.JPG 
Views:	38 
Size:	234.0 KB 
ID:	287917  
    Quote Originally Posted by Katman View Post
    I reminder distinctly .




    Kinky is using a feather. Perverted is using the whole chicken

  15. #75
    Join Date
    1st February 2004 - 11:00
    Bike
    MG V11 Nero Corsa LeMans
    Location
    out west a chch
    Posts
    9,469
    Quote Originally Posted by husaberg View Post
    I Swiped part or all of this
    cool, nice find... my MT125 replica was built in 77 in the back yard of a chch house, as no one here could aford the real thing this replica was modeled on the MT I think it wears Yamaha cloths, the engine was the CR125 elsanor, it won many a nz nat meetings... now the frame has been butchered and a hot MB100 engine sits on board.

    Click image for larger version. 

Name:	xx.jpg 
Views:	63 
Size:	41.2 KB 
ID:	287918 Click image for larger version. 

Name:	DSC_0176cutxx.jpg 
Views:	64 
Size:	23.8 KB 
ID:	287919

    ohh yeah the forks are now GT125 and the swing arm is a choped 125T, so fark all MT left.
    cheers DD
    (Definately Dodgy)



Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •