Author Topic: RT1 bite  (Read 12943 times)

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Offline Iain Cameron

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RT1 bite
« on: November 23, 2013, 07:26:23 pm »
Have not played with my RT1 for a while so dug out a DT400 ignition system and wow it runs . Shut it down tidied up the wiring went to start it and the bitch bit me I had steel caps on but the lever came back up my shin  :'( :'( :'(  I swear this bike hates me . Iain
Yamaha tragic ; dt1, rt1, dt2, rt2, dt2mx , rt2mx , mx250, mx360,sc500, 74dt125, yzx125, yzc250, yzc400, yzd250, yzd400, yzh250, yzh80 , dt100 , xr75 ko xr80 03 , it175 82 . Not a member of any club

Offline Andrew L

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Re: RT1 bite
« Reply #1 on: November 23, 2013, 11:40:53 pm »
I have a modified Rex's speed shop one on mine, the pulserless kit with the backing plate now supplied had to do some mods to fit it (the dt360\400 has smaller main bearings and seal so had to machine to fit rt3 also the mounting slots are a mile out but can be moved)has advance while starting so as to not run backwards and retards the harder you rev it and I can start it no problems while standing beside the bike in runners good mod couldn't do that with the points dislocated ankle and hip for sure.
"You have not made any mistakes if you find extra pieces after assembling an object. In fact you have just found a way to make the object more efficient."

Offline OverTheHill

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Re: RT1 bite
« Reply #2 on: November 24, 2013, 09:46:54 am »
have a similar system on my RT3 & 'never' kicks back. Pull the flywheel to double check it hasn't sheared off the key, especially if it didn't kick back on initial start up after fitting the 400 system. I hold the flywheel solid with a tool that inserts in the flywheel slots & rests on the footrest [or somewhere]. My 490k arrived in a similar state--first kick & broke the idler gear [& more], guy said [after this happened] oh i changed the stator before sending the bike & my compressor was low [rattle gun], said it started ok but had shorn off the key virtually as it stopped i think. My RT1 flywheel points ignition has an advance retard mechanism incorporated into the points cam. Think all pics relating to this is in my photobucket thing if you can find a link to them somehow from one of my posted pics. Hope this reads ok, damn keyboard playing up. Thanks.

Offline OverTheHill

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Re: RT1 bite
« Reply #3 on: November 24, 2013, 10:16:38 am »
found the flywheel holding tool pic on page 17 of my posts.

Offline firko

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Re: RT1 bite
« Reply #4 on: November 24, 2013, 10:25:20 am »
I remember back in 1970 when I raced my RT1MX, I had a little bubblegum tin chock full of flywheel keys, 'borrowed' from the machine shop store at work. It seemed like it sheered one every second time I kicked it. Of course that was back in the days before I discovered the science of lapping the flywheel to the crank with cutting compound. I've got a DT400 ignition with a Rex's Speedshop black box on my Cheney but a stator failed at the Nats before I could try the setup. I'm thinking about fitting a lighter flywheeled '92 YZ250 ignition to the RT2MX motor in my flat tracker (or to the Cheney, whichever bike it suits best) and was thinking of using a Rex Gaunt black box on it as well.....With my catshagged old knees I don't want to go through what Iain went through yesterday every time I kick either of them. In my 45 years involvement in dirt bikes I've had some really ornery kickback specials (SC500, TM400, 440 points Maico to name but 3) but the piston port RT1 Yamaha is the grand poobah of the kickback club. They hurt.

Mavman, is the setup pictured below the one you've used? Despite the fitting problems is it a worthwhile conversion? I've used just the Rex's black box on the stock DT400 stator but now wonder if my not using the Rex's full kit is part or the whole of my troubles. I've read good reports on the Rex setup which is what prompted me to use it in the first place so any input would be great. I really want need these two 360 Yamahas to start easily, added performance would be a bonus.
                                                                               
« Last Edit: November 24, 2013, 10:27:07 am by firko »
'68 Yamaha DT1 enduro, '69 Yamaha 'DT1 from Hell' '69 DT1'Dunger from Hell, '69 Cheney Yamaha 360, 70 Maico 350 (2 off), '68 Hindall Ducati 250, Hindall RT2MX, Hindall YZ250a , Cycle Factory RT2MX flat tracker, Yamaha 1T250J, Maico 250 trials, '71, Boyd and Stellings TM400, Shell OW72,750 Yamaha

Offline pancho

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Re: RT1 bite
« Reply #5 on: November 24, 2013, 12:50:14 pm »
I took the kickstarter off mine!
 If I can't find a pusher the bastard can stay there!
cheers pancho.
dont follow me i'm probably off line!

Offline Hoony

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Re: RT1 bite
« Reply #6 on: November 24, 2013, 12:53:31 pm »
are they really that bad ?
Long time Honda Fan, but all bike nut in general, Big Bore 2 stroke fan.    http://www.youtube.com/watch?v=XJoKP6MawYI
1985 Honda CR500RF "Big Red"
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Offline firko

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Re: RT1 bite
« Reply #7 on: November 24, 2013, 01:36:46 pm »
Quote
are they really that bad ?
Yes ;D
'68 Yamaha DT1 enduro, '69 Yamaha 'DT1 from Hell' '69 DT1'Dunger from Hell, '69 Cheney Yamaha 360, 70 Maico 350 (2 off), '68 Hindall Ducati 250, Hindall RT2MX, Hindall YZ250a , Cycle Factory RT2MX flat tracker, Yamaha 1T250J, Maico 250 trials, '71, Boyd and Stellings TM400, Shell OW72,750 Yamaha

Offline Iain Cameron

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Re: RT1 bite
« Reply #8 on: November 24, 2013, 01:51:07 pm »
are they really that bad ?
Hoony just make sure the bars are turned to the left when you kick one as bending the bars with your knee is painful . There are ways like dt400 ignitions ( I had not set it spot on) . They also can rip the kick shaft right out of the cases if they are in a bad mood . If you run a high comp head like the RT2MX without a decompressor you can almost stand on the kick lever (Im 80 odd kg ) not good if you have a doggy knee . But even with all their faults they are a fun bike . I know most others will not agree except Firko and other likeminded DT\RT tragic's . She is not standard by a long shot but in my eyes she is lovely .
« Last Edit: November 24, 2013, 01:56:58 pm by iainyz »
Yamaha tragic ; dt1, rt1, dt2, rt2, dt2mx , rt2mx , mx250, mx360,sc500, 74dt125, yzx125, yzc250, yzc400, yzd250, yzd400, yzh250, yzh80 , dt100 , xr75 ko xr80 03 , it175 82 . Not a member of any club

Offline firko

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Re: RT1 bite
« Reply #9 on: November 24, 2013, 02:44:41 pm »
Unless you've experienced the RT1 you'd probably think we're exaggerating but here's some other thoughts on the subject starting with Matt Cuddy's reminisces on the RT1's kick back from.....http://articles.superhunky.com/4/109

Endowed with a motor that was strong enough to pull street bikes up to eighty miles per hour, the 360 was plagued with some funky designs that you either loved or hated, one being the kick start design that exploded more ankles than land mines in Cambodia.

You had to use an exact starting drill to crank over the 360, or it would kick back, and send your ankle flying into the sharp seam on the exhaust pipe at mach III. This would cause intense pain, shooting stars and loud blasphemous curses to fill the air, as you hopped around waiting for the pain to subside, and circulation to return to your foot.

Many the times a classmate would want to ride my 360, and I would hand over the keys and say “you can ride it, if you can start it.” Not a whole bunch of my fellow classmates got to ride the 360, as they limped to the nurse’s office for an ace bandage. It even blew the Stan Smith right off one guy’s foot, and left a giant purple bruise on his in-step. Not for wimps


Or this off the Yamaha Owners forum:
Been down three days now after the RT3 nearly broke my foot/ankle/leg/torso/spirit with a couple of vicious kick-backs whilst trying to start. Being a lazy American and with the 'fiscal cliff' just now narrowly averted by my government, I never sprang for a timing light and have gotten by on setting the points to their nominal clearance per the shop manual. Obviously this has not worked out very well, so have finally ponied up the dough for a static timing light. It is my fervent hope that I will find the timing set at something like 6 or 7 mm BTDC instead of the requisite 2.9 mm.

 Anyone had any experience with the RT/360 line in this area? If I can't get this sorted the thumper will be sold - broken bones for someone born in the 50s just ain't gonna fly. :crying: Will most or all of the kicking back disappear if the bloody thing's timed correctly, i.e., head off, 2.9mm BTDC, points just opening?


Or this from Motorcyclist Online:

I’ve wanted a Yamaha RT1 ever since I saw Danny Alverez riding his black 1971 model back in grade school. That motorcycle was an unholy beast fit for hell raising and finger pointing. Only the strongest kid could dream of starting the RT1. Heaving down on the kicker with all my 85 pounds would yield a moist, phlegmatic cough, followed by an unsatisfied looking fuel cloud wafting accusingly from the Yamaha’s tail pipe. It was a look that in married life I would come to know all too well.

If the Yamaha didn’t break my leg, it wasn’t for lack of trying. The harder it kicked back, the more timid I would become. This strategy fed the bike’s remorseless evolutionary mission to kill off the halt and the lame. I had as much chance at internal combustion with Alverez’s RT1 as I had strapping down a struggling, cat-suited Emma Peel from “The Avengers.”


Read more: http://www.motorcyclistonline.com/features/columns/122_1210_yamaha_rt1_cranked/#ixzz2lWwLzsn8 



'68 Yamaha DT1 enduro, '69 Yamaha 'DT1 from Hell' '69 DT1'Dunger from Hell, '69 Cheney Yamaha 360, 70 Maico 350 (2 off), '68 Hindall Ducati 250, Hindall RT2MX, Hindall YZ250a , Cycle Factory RT2MX flat tracker, Yamaha 1T250J, Maico 250 trials, '71, Boyd and Stellings TM400, Shell OW72,750 Yamaha

Offline Iain Cameron

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Re: RT1 bite
« Reply #10 on: December 25, 2013, 04:05:37 pm »
Just a update . After taking the head off and dial gauge setting the timing ,new plug , new fresh 98 fuel at 32 to 1 .( Ha you thought I was writing this from my hospital bed didn't you ) She started first kick ran like a Swiss watch , Damm this cant be my Rt360 someone has swopped it , So I shut her down and tried to start her again . now you think you know what happened wrong , first kick brrrap we have life and Im still walking all the red stuff is inside no broken bones no bruising . Now to tell a story about this sweet bike (possessed monster ) built by Nifty how in hell( who weighs less than a YZ80) could  even kick the lovely girl over beats me . First race after picking her up she decided to break the backing plate location  bolt on the rear wheel , after unwrapping the break rod from around the wheel raced the next 2 races less a rear brake thank god Im a slow poke but it was interesting . Next event the 2011 Nats like Uncle Firko perfect before loading got over to SA nothing no spark , You know who sat there all weekend looking pretty and not getting dirty . next event 2013 HBBB dito same as 2011 Nats . So now you know How happy I am that my sweet good tempered girl is running . Roll on the 2014 Nats  and if she decides not to behave there will be an Evil bad tempered sadistic RT1 360 for sale . Iain
Yamaha tragic ; dt1, rt1, dt2, rt2, dt2mx , rt2mx , mx250, mx360,sc500, 74dt125, yzx125, yzc250, yzc400, yzd250, yzd400, yzh250, yzh80 , dt100 , xr75 ko xr80 03 , it175 82 . Not a member of any club

Offline oldyzman

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Re: RT1 bite
« Reply #11 on: December 25, 2013, 08:19:28 pm »
I remember when Nifty built and put that GMC pipe on it in about 2010 at nepean. Nice looking unit. Have not seen nifty for a while now..
Brett
I have a soft spot japanese mxers with aluminium tanks. Two stroke classic Dirt Track...

Offline Iain Cameron

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Re: RT1 bite
« Reply #12 on: December 25, 2013, 08:33:15 pm »
We still talk once in a while but he got dissolutioned  with his club combining the 125 classes as that was his main class , He still does a bit of flat track once in a while . Nev and I started at Heaven together and for years we teamed up at meets . I miss the bugger since Ive moved to Tassie . Iain
Yamaha tragic ; dt1, rt1, dt2, rt2, dt2mx , rt2mx , mx250, mx360,sc500, 74dt125, yzx125, yzc250, yzc400, yzd250, yzd400, yzh250, yzh80 , dt100 , xr75 ko xr80 03 , it175 82 . Not a member of any club

Offline oldyzman

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Re: RT1 bite
« Reply #13 on: December 25, 2013, 08:39:51 pm »
I purchased the rm125S off Nev and he geed me up to do DT at Nepean.
Neville is a good guy.
Brett
I have a soft spot japanese mxers with aluminium tanks. Two stroke classic Dirt Track...

Offline firko

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Re: RT1 bite
« Reply #14 on: December 25, 2013, 09:26:40 pm »
Nifty's a good bloke for sure. It's ironic Iain that you ride his old pre 70 RT1 and he now rides my old 250 square barrel Maico in the class....He's a bit pissed off that pre 70 is combined with Pre 75 125 at HEAVEN meetings, thereby blocking out his only other ride. You see him more at the dirt track these days.
 
'68 Yamaha DT1 enduro, '69 Yamaha 'DT1 from Hell' '69 DT1'Dunger from Hell, '69 Cheney Yamaha 360, 70 Maico 350 (2 off), '68 Hindall Ducati 250, Hindall RT2MX, Hindall YZ250a , Cycle Factory RT2MX flat tracker, Yamaha 1T250J, Maico 250 trials, '71, Boyd and Stellings TM400, Shell OW72,750 Yamaha