Bigbore stroker 277 part 10 - Install, will it run?
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- čas přidán 29. 01. 2018
- In this episode I install the engine in the sled, do some fuel stuff, and try to start it!
PS: What you see in the video is the actual very first start with the new sleeve, no cheating or editing magic involved, it was the first time I pulled the rope (with the intention of starting) since the rebuild. I did use the primer off-camera before I hit record, and the carb was already somewhat setup since last months attempt with the old broken sleeve.
Check out my Instagram at / hollaendaren
Spoiler alert, Instagram is going to be a bit ahead of the videos.
Music: Russki Psycho by The Vivisectors - Auta a dopravní prostředky
Awesome!
2STROKE STUFFING Thanks man! And hopefully this is just the beginning :) Definitely beat the 2 minutes longevity record today.
I'm going to put in a smaller idle jet tomorrow and see where that gets me because it seems to start running cleaner at the end with a little bit of throttle. If that doesn't help, maybe the float level is wrong. Or maybe the choke disabling plug that a previous owner of the carb put in there isn't quite working and it has full choke all the time.
We'll see, can't be too hard to fix.
Looking forward to a test ride!
Your sled and tricks remind me of a friend of mine Ron Hornack who has passed on. I see the stinger and that’s one of his ideas he thought of but I never were to try modifying my carb with a screw in. Also I love your trigger setup with the battery that’s another invention he made come to light years ago.
You sir are a true mechanic!! Great job your work is amazing!! New subscriber
Thank you :)
Ok good to know, the elan chain is in very good shape.
nice! getting a freshly build engine to run is the best
jnuxca Definitely! I hope it stays together but looking very promising so far :)
Can only agree with 2STROKE STUFFING, Awesome! It´s really nice when you first heard the engine beginning to talk to you "More revs!!". And seeing it start on the first pull... pure joy! I think you thought so too but I'm not good at sign language. ;)
Alexander Jäderblom Thanks! Yes I was pretty excited about it ;) I was trying to signal "first pull". I'm thinking I should open it up and take a look at things before I give it full throttle and high rpms.
Hollaendaren Yeah I'm not saying you should rev it, but the engine definetly likes a little more rpm, i guess the pipe is made for it and the timing too. Would like to lear more about tuning and i own some books about it. Good idea checking it out first, would have done the same. :)
Good work. Any tutorial on the ignition system? I would love to watch that.
I Like your works very much, awesome... And Great machinist! Just a question, which timing you have in this big piston port rotax? Hoping in more videos..
Vns workshop thank you! Currently I have 28 degrees at 6000 rpm, ramping down to 18 at 9000. It's going to need adjusting though.
Yes! That’s a success! The sound is just insane without baffles, proper deafening! Looking forward the crank balancing too. Is it dumb to think you could add a balancing weight OUTSIDE the crankcase, ideally symmetric weights on both sides?
Benoît Genest That's why I have ear protection ;) ear plugs while riding. You should hear my 797, when riding slowly through the pit at a race people start covering their ears when they see it coming :D
I think that's hoa modern 2-strokes do it, an external balancing shaft driven by a set of gears. I'm mostly into old stuff as you can probably tell. But might be worth having a look at in the future!
My minibike with an old Briggs flathead actually has an internal balancing shaft inside the crankcase, but that's a 4 stroke.
The 797 is a dream machine! Hope I get to see and hear one in real life one day! Another solution for balancing would be investing in a titanium rod ;)
Benoît Genest It's my dream machine too :) has been highest up on the "coolest sleds of all time" list for a long time! I'm counting myself lucky that I had the opportunity to buy it a couple of years ago.
Titanium sounds too hi-tech for me, and expensive ;)
Great vid ! No clutch or gearbox?
Thanks! Nope, it has a CVT transmission :)
Congrats on getting it running. Next garage improvement: exhaust outlet.
DrBOB101 Might be time for that.. ;)
The engine you will found That boost port is tm K2 125 Kart from 1980'
That motor has the most beautiful ignition crack coming out of the exhaust pipe music to my ears wow wonderful job that motor is going to get after yo momma atb Russ
Thanks! My cameras microphone really doesn't do it justice, it has an awesome sound! I think the twin plugs may be partially responsible for that, I use 2 different plugs, and 2 seperate coils, so they are likely not firing at exactly the same time so I think that might add a bit of "depth" to the sound.
Does that run 2 coils standard ?
AuMechanic This engine has a single plug standard, completely different head. The dirtbike that the head is off seems to use a single coil with 2 outputs as far as I can tell. I ran a coil like that on my old engine (same type head) but I wanted to switch to MSD ignition and they told me the dual output coil was discontinued so I'd have to use 2 single coils instead.
I've connected them in parallel to the output from the box, not sure what's better, parallel or in series, but so far this seems to be working.
That could be a problem
I've tried using 2 coils on a twin optical ignition system on my racing RD350LC Yam in the 1980's
Result was poor ignition current, would not rev out, and fouled on one plug at low revs.
I removed one of the optical (Lumenition) systems and used only one unit connected to a twin lead coil off a non CDI 4cyl 4 stroke GS750 (induction ignition not CDI), the original RD twin lead coil was for CDI so couldn't use that.
That sorted it and never fouled a plug again and one system only used less battery power and I had no alternator on it.
If the MSD is an induction system you could use a 4t 4cyl twin lead coil of an older bikes with points or try to source a twin lead coil for induction spark system.
As to why, the twin lead coil has a positive and negate firing plug and each plug grounds through the other, it is not 2 coils in one, (i have a video on how they work) this means that the secondary current is always present at both plugs even if one is fouled, which is desirable in both twin plug and twin cylinder.
In 2t twins the twin lead coil runs as a dead spark system, but likewise current is always present at both plugs.
A lack of current through one plug that is fouled (a spark must occur at some point to generate secondary current) leaves no means to clean itself.
AuMechanic Thanks for the explanation, I'll check out that video later! On the old engine I've ran 2 coils in parallel like I have now with good results too, one coil gave up on me though probably because of vibrations (it was mounted on the crankcase) but the engine still ran okay on the other coil/plug, I actually didn't immediately discover it was broken. I didn't have a spare coil of the same type laying around so then I tried a dual coil instead, which also worked fine.
From what I can tell by eye these coils seem to give me a stronger spark than the previous setup, nothing scientific though, just eyeballing. I've read that using different coils are a popular upgrade for Ignitech to fix its relatively weak spark so there's probably something to it.
A guy on Instagram told me he runs a 2cyl Ignitech box connected to a single MSD coil with good results too, he runs funny fuel and very high rpm compared to what this thing will be turning.
So I'm hoping for the best, just need to sort out the jetting and bolt the chassis back together and then I think it's time for a proper test ride.
Have you calculated the displacement with the new bore and stroke?
snocrushr It's 335 cc now, from 268 stock.
will a stock 72 elan chain case hold up to a stock 440, with around 30hp? Im swaping in a 440 out of a tnt in to my 72 elan, i do have the tnt chain case as well.
Christopher Blair I think a single row chain should be fine for that as long as the chain is in good shape. I use a chaincase and chain off a twin Elan on this one, with duplex chain. Never broke a chain so far!
What gearing do you run on Oly for drag racing and the hill climb? Can you change upper gear by one tooth without changing the chain? What do you do?
William Lunney I'm not sure about the exact sprocket numbers but for hillclimb I gear 2 teeth lower than for drag racing. I think a 21 upper for drag and 19 for hillclimb. I have a little extender piece for my chain that I put on for higher gearing, basically just 2 master links in a row because as you probably know replacing the entire chain is a bit of a hassle on these things :)
Thanks!
Congrats! 👍 That is a really low balance factor. I’m sure you will get it right in the end. Interesting project on it’s own. But a fair bit of work. Maybe you won’t need to alter the BF if you run at a rpm not effected that much?
andli461 Thanks! I'm a happy camper today :)
I know it's really low, but that's what a longer stroke, heavier rod and heavier piston did to that 20% it has stock. Which seems very low too btw.
But that's what I'm hoping, if I can get low enough idle speed, and high enough engagement maybe it'll work as it is. Same problem with the stock engine, but the shaking is spread over a wider rpm range now.
Hollaendaren Hard to say what will happen really. But of course, getting something more “mainstream” like say 50-50% would probably not hurt. But then it’s about the “frame” etc etc so what is ideal is hard to say. Trail and error.
IIRC, older foul stroke bikes whit a vertical cylinder often run up to 70% bf. Just got to think about it. You better double check that though.
andli461 The stock 20% has been working great in previous years, so I know that will probably work this time too. But I have an old Husqvarna 250 dirtbike that has an almost vertical cylinder and its crank is around 50%, can't remember the exact number. But we'll see, I need to take a test ride before I do any crank hacking :)
Hollaendaren Get what you are saying. This is no obvious thing to “just do the calc and follow the result”. Way more complicated than that. So absolutely, give it a go! The 20% stock bf must be there for a reason. 👍
andli461 Yeah I figure there might be a reason for it. I will be turning it around 9200-9400 rpm with the new pipe, so as long as its really smooth there I'll be happy :)
sounds Mean man MEAN awesome!!
Thanks! I'm looking forward to hearing it at full throttle and high rpm! :)
Hollaendaren yes man ThaT Rotax is Like music to my ears ! czcams.com/video/IvUU8joBb1Q/video.html
Hey I have a rotax 277 on a scat hovercraft any idea on how to size a carb? I was wanting to run a mikuni
I'd say for a stock engine a 34 would be plenty, maybe a 36.
its alive its alive!!! 😆
15taggarn Finally :)
I forte to say That the design of your intake port and the small ring holder è is very clever, i never saw it, really cleaver your idea! But why not just bridged port on the sleeve? Maybe because of your piston design. howewer Great exstreme work!Only things you need boost port in front of your exsaust port making wawe better work with crankase exstraction. With piston port not easy but you need... I have exsperience with old piston ported 125 cc Kart engines, Take a look to tm 125 Kart portmap! Good luck
Vns workshop the piston skirt is too narrow for a bridged piston port, I would lose area by doing so. I considered boost ports for the exhaust but the studs are in the way for the boost channels so they won't work either. So I had to stay oldschool :)
Ok, all is very clear now and make sense, you have a great approach in tuning and study engines!!
Great, i stay tuned on your channel !
What’s the deal with the adjustable main jet? You should make a video on that sometime.
I've made it for this project, haven't really gotten to test it properly yet. I'll do a report on it after I've actually tested some full throttle action :)
I just mentioned what it was because otherwise the question would inevatably come up anyway.
I'm interested in your adjustable jet too, some of my old Puch mopeds have a adjustable mainjet too. Pretty simple actually, some holes and a needle that adjusts the flow. I guess yours is similar, a taper bored jet and a needle that adjusts into, or what? :)
Carsten Lorenzen Exactly like that :) I just need to get the low speed jetting sorted out first and then I can test this one :)
I need engine sir please mail me.
Sorry, it's not for sale.