| Author | Message | ||
     Newfie_buell |
OK, I was always attracted to the Two Strokers so last night I took the opportunity and gambled on a 1977 Yamaha RD400. I am the second owner with the first one having parked this bike 18 years ago in the back of an unheated garage. The owner of the garage would kick it over about once a month to keep it from siezing. At first there was no spark but it did kick over. I thought OK there are no cams, chains, valves or any other stuff up there so how hard can it be. The carbs were stuck as well. Got it home, lubed the carbs and the slides now work, took them off and OMG what a mess of old two stroke oil and crap. Dis-assembled both carbs and currently have them soaking in degreaser/cleaner. Amazingly after 18 years of sitting in the crap they were pretty easy to take apart, I figured the two stroke oil that was in them attributed to their preservation, not one siezed screw or jet. Popped off the points cover and noticed the points had a nice powder/corrosion on them, cleaned them up with a bit of fine sand paper, kicked it over and plenty of spark. All Lighting is working and the bike is all original with the exception of a set of rusty DG pipes with expansion chambers. I'll pull them off, clean them up and repaint flat black. Its in bad need of a cleaning but I want to go with a Cafe Racer Type of machine. The chrome fenders have surface rust spots as do the grab bars, no rust on the forks and the seals look to be ok for now. No front brake but that seems to be a problem up in the master cylinder. I'm open to suggestions!!!!! If anyone has any suggestions please post. Also, I am familiar with hopping up a four stroke bike but what the heck can I do with a two stroker. | ||
| Buelluk |
Newfie, I am in the same place as you , I have a 1976 RD400 , it's not running or doing anything at present, but i have bought lots of old and new stuff for it to convert it into a cafe bike as well ,i don't ever seem to find the time at the moment, however here are two sites for advice: http://www.aircooled-rd.com http://www.yamaha-rd.com/ You can also try MotoCarrera in California for lots of standard and tuning parts and Ebay is also a great source as usual. Let me know if you have any other questions. | ||
| Loki |
keep those DG pipes and think later model RZ body stuff. and to think the rz350 mill is still kickin these days in a quad. http://www.aircooled-rd.com | ||
| Loki |
see what happens when people thinks alike | ||
| S1eric |
I use to race those old RDs. Those DG pipes run pretty good. Try A set of fiber reed valves. I think Boysen still makes them. Clean up the ports in the cylinders, But dont go crazy in there, You don`t want the piston skirts to catch in the ports. You can also cut you pistons to get more fuel ( faster ) to the combustion chamber. Rd 350 pistons will work in the 400. only the stroke is different. I`ve Built quite A few of those motors. I have A whole library of old hop up books from the 70s hanging around, Let me know if I can Help. In the looks department. I always ran TZ 250 bodywork. I still have some in my attic that I was going to use on my S1. But Airtech still makes the TZ stuff. S1Eric | ||
| S1eric |
You guys got me thinking about those old 2 strokes. On the porting thing, If you raise the intake and lower the exhaust you get A really good midrange punch. Dont mess with the transfer ports. I have all of the diagrams and specs for cutting or modifying the pistons if you want to go that route. But I always found the stock windows cut in the pistons worked ok. Those DG chambers work just fine,But are kinda middle of the road. If your looking for real power out af an exhaust sytem, Call Gary at spec 2. He will make you A set of chambers for your needs. Spec 2 might also sell an electronic ignition for your bike, But some don`t advise it. A two stroke motor can actually run backwards with it. But only if it gets bump started in the wrong direction. S1Eric | ||
| Aldaytona |
You guys hit the FUN jackpot. | ||
| Newfie_buell |
Its ALIVE Hey S1Eric - I would appreciate whatever advice information you can give me. I'll ping ya with my email address. Its missing on one cylinder but I suspect that lack of a battery and dirty points would cause that. Yeeeeeeeeeeeeeha - I just love the sound and smell of a two stroke. | ||
| Cyclonemaniac |
Run some Klotz thru that baby. It'll smell really good then. I've been wanting a ring-dinger for some time now. I had some serious lust for the RD400 when I was in Hi school. First street bike I was ever on was a Kawi H1! Now there's a real "starter bike"!  (Message edited by cyclonemaniac on September 30, 2005) (Message edited by cyclonemaniac on September 30, 2005) | ||
| Aldaytona |
Global warming, Ozone hole, nah, I think the EPA ban on two strokes was the beginning of the end............................................ Can't have those pesky 250-350cc engines polluting the air, we have millions of Hummers-Excursions-Escalades ect. to do that, all getting 10 mpg driving around with 1 person on a cell phone. | ||
| S1eric |
Newfie You have mail. S1Eric | ||
| Rek |
yeah baby! I picked up a Suzi GT 750 under similar conditions a few years ago. It had been sitting for 10-11 years in an open carport. All I had to do was remove the carbs and clean them really well, replaced all the fluids, install a new battery. She cranked over on the third try, been running like a banshee every since. Have fun Rob | ||
| Mr_grumpy |
Bill, Do you have Redex there? If so squirt some down the plug hole (or one of the old oil based fuel additives like stp or wynns) & let soak overnight to make sure the rings aren't stuck, also make sure the oiler pump is working properly, It may need cleaning & priming after all this time. That's about the only thing to go wrong on 'em other than that they're just about bullet proof, oh & make sure you've got the right plugs in, I ran nothing but strokers in the 70's, I wouldn't mind another one too, ebay here we come. If you need a manual look here, http://www.repairmanuals.com/motorcycles/1977/69/4/2902 Mmmm I can smell it from here,  | ||
| Newfie_buell |
Remember Mark, He now refuses to stop behind me in traffic due to the 2stroke smell. Redex, never heard of it, but I am willing to try the other stuff, the pump appears to be OK s the oil leve was lower in the tank tonight. Also, Are two strokes terrible on gas!!!!! Someone put a set of pipes on it and I think its causing my sputtering over 6000 rpm. I may need to rejet but I will eventually find it and how to tune this thing. Its a real fun bike though!!!! | ||
| Mr_grumpy |
Ah well, at least you've now got something that I CAN kickstart. | ||
| Newfie_buell |
Yeah, Even my 14yr old daughter can start this one!!! She has been sneaking out to the garage every day starting it. She really got the itch to ride it and wants me to save it for when she turns 16. She told me it was kinda retro and funky. Anyone got any ideas on what to run for jets - those with two stroke experience. | ||
| Jackbequick |
Sputtering? Like four stroking or too rich? If so, you might try looking at the position of the clip on the needle(s) in the carb(s). If it is running okay up to wide open, it maybe be that the needles are too high and it is getting too rich with the needle fully lifted. Those would typically have 3 or more positions, I'd try it in the middle position if it was clipped any lower (needle higher) than that now. On the pipes, are those like expansion chambers? With a moderate sized inlet, bulbous in the middle, smaller/longer outlet? If not, that may not have the right exhaust system. Or even the right kind. Two strokes need some back pressure in the exhaust cycle to run right. If they have painfully sharp report they may be the right kind. :>  Jack | ||
| Mr_grumpy |
Another thing to check may be the headers need decoking, if they're all built up with c**p on the inside they'll restrict the breathing at the top end. A common stroker problem due to all the unburnt oil & gas that gets pumped through the system & condenses on the inside of the pipe; | ||
| Buelluk |
Newfie, If you go to http://www.aircooled-rd.com they have lots of tech stuff on jetting. As far as being bulletproof , just watch the timing , holed pistons are common with poor settings. BTW you should be able to start an RD by hand ! (Message edited by buelluk on October 05, 2005) | ||
| Newfie_buell |
Thanks for the link, Been there and will start my finer tuning this weekend. Any suggestions on how to eat the crap out of the pipes, a good cleaning wouldn't hurt. | ||
| Buelluk |
We used to flush our pipes and baffles with gas to get the stuff out ..not really the safest way to do it though. | ||
| Bomber |
Grumpy -- only an Englishman would say decoking without a straw in his hand! | ||
| Mikej |
Apart from the gas burning in the pipes, used to do that myownself, you can also try a solution of fine gravel and some sort of grease disolver. remove the pipe from the bike, plug one end somehow, fill pipe partially full of the slurry, cap the other end, and go do the HokeyPokey dance in the yard as you slosh it around cleaning the inside of the pipe out as best as you can. We used to use gas or paint thinner, but we were young and dumb back then. Be sure the inside of the pipe is well rinsed out with water and left to dry well. We also used to use my dad's oxy/acetylene torch on them along with a wire brush when he wasn't home, of course the pipe either wasn't chrome (on one bike) or didn't stay chromed (on another bike) once we were done with them. And how you dispose of the residual mess is entirely up to your own doing as these days things would be done much differently, allthough I'm sure I'd still use a torch at some point of the process even though my Hokey Pokey dance is best left for days long gone by. | ||
| Natexlh1000 |
I saw an article in a British bike mag in which the author heated the pipes in a gas barbecue grill until it started to smoke. He then applied a vacuum's blower to one side and FLAMES shot out the other side. He stopped when he saw it start to MELT the aluminum muffler! I would suggest taking off the muffler  | ||
| Buelluk |
As MikeJ said, in England the grease dissolver we used was called Gunk..I don't know what the equivalent in the US or Canada is. (Message edited by buelluk on October 05, 2005) | ||
| Mr_grumpy |
I always used to used a solution of caustic soda, (protective gear a MUST) but I've seen gas used as well. If you can get a flexible round wire brush to do the inside, that's good too. Kinda like cleaning a, big, bent, shotgun. | ||
| Newfie_buell |
Caustic Soda poured in should eat away any coke. Where do I find Caustic Soda? | ||
| Diablobrian |
should be available at your local hardware store | ||
| Newfie_buell |
Big Bent Shotgun, Didn't ACME sell one of those to the Coyote to get the Roadrunner!!! | ||
| Mr_grumpy |
ALWAYS read the instructions. |
