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RT3 kick-back


flyday58
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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?

I used to have a gen-u-wine strobe timing light, but sold it sometime after selling the last points car I owned. Must have been the 1969 Mustang. Wery similar to a DB9; you've probably seen them around. :D

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Ahhgh ouch oops, yeah but isnt there some timing marks on the rotor and crankcase, these are usually fairly accurate, try a cigarette paper pullout as these line up? I assume the RT3 has a magneto ignition being a dirt bike and all that?

Whats your kicking technique then Richard?

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Ahhgh ouch oops, yeah but isnt there some timing marks on the rotor and crankcase, these are usually fairly accurate, try a cigarette paper pullout as these line up? I assume the RT3 has a magneto ignition being a dirt bike and all that?

Whats your kicking technique then Richard?

So you have to be a Moderator to get those cool tie-dye effects on your profile piccy? :spin2:

Using the marks on the magneto rotor and case has always worked just fine, except for this beast. I will try the cig paper pull bit; obviously using a multimeter doesn't work. I truly haven't been able to get a good solid indication of points opening that way; maybe I don't have the points properly isolated? I did disconnect the condenser wire at the points.

My kicking technique is to stand on the right of the bike and kick hard with my left leg. My right leg is weak from a grammar school-age injury, so it can be hard to start even the little DT whilst aboard.

Since this is a two-stroke, is there a preferable position for the piston prior to kicking to alleviate kick-back? Even with the decompression lever all the way open there's still a hefty bit of compression, and I have verified the the valve is, in fact, decompressing.

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yeah you should push gently and you'll feel compression, continue to push gently through the lions share of that compression until you're almost TDC, then give it all youve got and the flywheel will have a bit of momentum as it hits the next compression stroke and so it will help you, I note that you are at some disadvantage though with the left leg fix you're in

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Thanks, will try that if my foot ever heals. Couldn't get around to using thin paper tonight as the wifey is down for the count and had to make dinner, clean the kitchen on and on and on. Getting old is hell.

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Ehm the condenser is droping it's charge to early...= bad condenser. Timing can't fix that.

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My DT400 had a auto decompressor , i found it annoying, i disconnected it, Two-strokes are easy kicked over compared to theXT500

theyre a real chalenge :yeah:

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My DT400 had a auto decompressor , i found it annoying, i disconnected it, Two-strokes are easy kicked over compared to theXT500

theyre a real chalenge :yeah:

Agreed, I had a 77 XT500 that I came to loathe more than gypsum board and mitre joints, which is quite alot. It was my one and only excursion into 4-strokes, and I know that most of my dislike stemmed from not understanding the bloody thing. I used it around here in the woods and on trails, and the gearing was just bollocks for that purpose. Plus, when I invariably stalled it, I kicked and kicked and kicked and then kicked some more before finally getting it to spark back into life. By then I was so pissed (angry) and worn out that all the fun was gone. Hated that thing.

I know now that I could have solved the hard starting issue by changing the timing chain, and a fiddle with the sprockets would have helped in the dirt. Kind of wish I had it back now! Aint' that usually the way. :eusa_think:

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some good multimeters will measure capacitance by the way...mine will ;)

Yar, myne won't. But the neighbor may have one that will.

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New static timing light came today, basically an on-off light that goes out when the points open. But I had to disconnect the condenser from the points for it to work, which requires removing the flywheel. With the flywheel off, I took a long hard look at the timing post bolted to the stator chassis, which you line up with a mark on the rotor/flywheel for points opening. I compared mine with several piccys on ebay. Turns out mine is bent. Alot. In the advance direction. :madflame:

My fault for not throwing EVERYTHING (assumptions) out the window when I bought this contraption. Don't know why it never occurred to me to check the post for straightness. It never looked right; I just never checked.

So now I've got it timed like I want it, very close to the required 2.9mm BTDC. The head had to come off to mount the dial indicator properly, so I will clean and paint it before reassembling. My foot is still not 100% so not in a hurry to bang away at the kicker right now anyway. Will update when it's all back together again.

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Great result flyday " :thumb: ,,, That static timing light, would a light holder and two wires do the same job ,,?

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Great result flyday " :thumb: ,,, That static timing light, would a light holder and two wires do the same job ,,?

Yer bugger! 'Tis just the same, but my shop is nearly as big as the shark cage from "Jaws" so no room to work, let alone store the 3 scooters I've got. It was easier to purchase one than try to bodge one together. My meter was basically doing the job but was a Congressional pain to keep the leads in place.

I doubt it John it will almost definitely be a flywheel magneto jobbie, so it's my guess this thing carries it's own batteries

Right on both counts Paul.

Got it back together today. Put on my heaviest-soled boots and gave it a go. Started up on the 2nd kick with no kick-back. I was too chicken to shut it off and try again, but I will try tomorrow before breathing easier on this one. I also used the past TDC position for cranking/kicking, seemed to work well.

So for now, yippee! :biglaugha: And Amy MacDonald is crooning "This Is The Life" on the stereo, what a deal!!

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Post a video of it running " i love the old RT1 exhaust note, like the TS250 savage,, :jossun:

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Yeah show us another one of your pullovers haha.... please :D

Paul, you know what? I...you...oh hell, never mind.

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  • 3 weeks later...

Looks like this one is solved. She absolutely had to be timed with a dial and timing light, with the head removed, per the book. No kick-back now, and runs and idles like that fabled beast in the land of Honiley. Lots of 'Puff'ing too, God bless the two-stroke! :elephant:

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Great news Flyday! :yeah:

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