I enjoy your light hearted and unusual projects. It is refreshing after a long stressful day. Don't change, and don't let the armchair quarterbacks get you shown down! Thanks
The stationary side of the CVT pulleys are opposite of each other, so the belt is being forced diagonally when the CVT pulleys change size. They are supposed to be in line with each other so that the belt drives perpendicular to the pulleys.
This is not correct. If you actually look at the belt on the video it stays straight, this is how CVT's are setup. I've messed with CVT's for years and they are all setup this way.
@@Braxel_watch the pulleys, not the belt. The two pulleys that are stationary are not on the same side. As the transmission shifts, the belt is pushed to the right by the top pulley, and to the left by the bottom pulley.
@@DullBoyJack With my reply i meant that the comment is incorrect because he seems to suggest that the stationaries should be on the same side which is wrong. yeah no its not being pushed to the left(bottom) on acceleration because the moving pulley moves out letting the belt ride lower. that all happens due to the conical shape.
When I was younger, I had a mini bike with a smaller version of your cvt setup, it was too steeply geared and would not rev out but I tightened up the driven pulley spring; acceleration and top speed improved, you should try this out for your next test. There should be three positions for the driven spring tension. The only reason for me mentioning this is because I hear your engine bog down about half way through 3rd. Tightening the secondary spring should keep the engine in a little bit higher rpm range through middle of 3rd gear. Doing this mod can be a huge pain but should prove worth it.
We do plan on changing the weights in the clutch, however we wont do that until the carburetor experiments are done. changing the weights now will also change the result of the carburetor experiments and we wont know if it was the carburetor of the clutch that made a difference.
@@robotcantina8957 I don´t think he´s talking about the clutch, the problem here seems to be the drive/top pulley engaging much earlier than the driven/bottom pulley, as the drive pulley expands faster than the driven pulley can retract the belt gets too much tension and starts fraying. If you really don´t want to adjust the pulley weights or springs, I guess you need a slightly larger belt to reduce the tension just enough that the belt stops fraying, but not so much that it starts to slip.
@@robotcantina8957 lighter weights could result in more belt slip while stronger springs would instead increase the internal stress on the belt. Pick your poison!
Hey, it's called R&D, Gonna be issues to get it right, That's why I love seeing the progression and how you overcome the problems, Keep up the great work! I would love to see this car made into a fully functional daily driver with this engine.
The arrow is to make it easy to reinstall the belt back in the same direction of rotation thus keeping the wear pattern of the belt consistent and not cause excess belt wear. Kind of like why you don't rotate radial tires from side to side changing direction of rotation.
I think you might be referring to directional tread tyres. The vast majority of tyres these days are non-directional, or asymmetric, meaning they can go from passenger side to driver's side without issue.
@@heath780391 General purpose / all season tyres maybe, but all the tyres I have fitted to all my vehicles are directional. I always use premium winter tyres in winter, and track style semi slicks in summer.
@@althejazzman Here in Australia / New Zealand, we generally have all season tyres, as the winter temperatures just aren't low enough, nor do we get enough snow to justify winter tyres. I'm a brand loyalist to Michelin, and in our market only the entry level products in thier range are non-directional, the rest of them are asymmetric designs (in what I've seen that is).
@@heath780391I'm in the UK and we don't have to legally use winter tyres either, except I tried them about 5 years ago and haven't looked back since. Much better grip in colder temperatures and better water displacement.
The CVT stationary halfs I believe should be on the same side, thinking of a snowmobile drive system. During the shifting you can see the belt angle bewtween the pulleys.
Yeah I went back a few times to check that out exactly. When I was just watching it looked pretty radical but when I went back it wasn't as bad a I thought but it was still there, good eye.
My snowmobile days are years ago but right the fixed sides are opposed, but often the secondary or driven clutch has float to it to maintain alignment. Center to Center is less critical than alignment. We had several tools that would drop in to check alignment on the secondary
I've been enjoying your videos for a couple years now. I do hope you know you don't have to defend your choices to the viewers. There will always be people who have opinions about how you're doing everything wrong. I guess what I'm saying is that in your more recent videos it feels like you are explaining and defending your actions to commenters who disagree with you. It's your channel, do what you enjoy. There are some people out there you can't make happy no matter what. As long as you are having fun building cool things I will always enjoy watching, no matter what kind of funky things you get up to!!!
There are already a couple of comments that mention the stationary side of the pulleys are incorrectly mounted opposite each other. The lower driven pulley needs to be turned around so that the sheave that doesn't move is on the same side that the stationary sheave on the engine is located. In the current setup the belt is being misaligned as it goes through the RPM. Also on the CVK carb I also think there's a small pilot type jet under the little black plug in the bowl. I think. Not 100% sure on that, but I remember at some point having to clean a dirty carb like that and there was a passage under it where fuel transferred from the pilot jet across to that plugged column. Great work and I love the content. Thank you for sharing!
The pulleys are mounted correctly for this 40 series clutch system. That's according to the Comet documentation. Indeed, some torque converter clutch systems have the driven pulley mounted backwards but on this system the default mounting is the way I have it.
I thought I could see the belt "rocking", but i watched it again a few times and it looks like its working right. Thanks for the quick reply! Hopefully it's an easy fix. :) @@robotcantina8957
I know there is always a better way of doing things but trying new things and analyzing the results (and sharing them!!!) makes it fun to learn about all the things that influence results. I can’t get enough; didn’t know anything about cvt or constant velocity carbs. Sincerely, thank you.
Good eye on the CVT!! May I suggest changing the weights in the CVT to change the timing of the engagement of the pulley? It would help keep the drive pulley in a lower ratio longer and giving you better acceleration. It will also help with the longevity of the belt by letting the belt not slip so much while staying in third gear and pup the engine in more of its power band
The belt deflection on that primary is absurd, can't say I've ever come across that issue unless I had the wrong size belt or my clutch sheaves were looking for some love and attention.
EDIT: In restrospect, it HAS to be like this for the belt to maintain alignment as it cycles, and after viewing a few different videos - it appears all CVTs actually operate like this. The difference is other CVTs are constructed differently with a different mechanism, so it LOOKS like this one is wrong, but it's not. ------------------- The real problem is you have the fixed side of belt sheaves opposite of each other. They need to be on the same side to maintain belt alignment. As you can see in the video as the CVT cycles through its travel, the belt gets more and more angled. Under high speed and high power, even a mild misalignment will burn through a belt fast. At close to top speed, your misalignment is very severe. You can see how it's rubbing hard on the belt edge, literally grinding away at the cords inside the belt. Unfortunately it doesn't look like it's possible or easy to flip the driven sheave around with how it's constructed. You might be able to compromise and slide the engine over, so the belt has better alignment under power with the trade off of having poor alignment at idle and low speed.
But didn’t you also say that you’re going above the rated power of the clutch? The mounting configuration might be fine at rated power but since you’re above it it might be exacerbating the issue. Although the spacing is definitely going to help and might just take care of it
@@robotcantina8957 Actually thinking about it, this is the correct way for CVTs to work. I think what threw me off is that it's of a slightly different construction style than other CVTs, so it looks like its backwards, but it's actually not. The angle the video was filmed at also makes it seem like the belt is misaligned, but it may not be. However Comet does have a specification for centerline belt misalignment - check to make sure it's not more than 3/8".
On a snowmobile you do want the belt to sit about 1/16” above the secondary sheaves. The 1/8” you have is to much. You also don’t use belt tension to adjust the ride height, you use spacers in the secondary so the belt is free below engagement rpm.
The engineering behind this build is unknown. If the secondary is bottoms before the primary, it's putting an excessive amount of tension on the belt. I'm not sure how this clutch is put together but I'd want to shim the primary so the belt doesn't come over the top at full rpm.
Thanks for the in-depth analysis of the the CVT. Yup, that drive belt riding above the pulley sure looks like a problem! Hopefully raising the engine a bit is all that it takes to get things working well again. The RU-vid comments section is always such a funny thing. Most people are cool, but you'll always get a few people who hate what you're doing and want to see something completely different. Whether it's the way you pronounce something, your pacing, your choice of various parts, or even saying "Why is you name Robot Cantina if you don't have any robots?" you'll always find some comments that can be summarily dismissed. Don't worry too much about responding to them either in the comments or in your videos - it only validates their poor behaviour. Meh, you can't please everybody all of the time, but the success of your channel shows that you are pleasing a lot of people all of the time. :)
What a rough day. I usually watch every Sunday morning after church and today was a very busy day. I am finally at 8pm getting to sit down and watch the dual carb showdown. Can't wait!. I look forward to your program each week.
We live near the Arcimoto factory in Eugene,Oregon- watching your experiments, makes me think, instead of a pure electric car, Arcimoto should build a hybrid car using a predator 620 cc engine. Gosh, wish you were an engineer working for the Arcimoto!
My first car was the 1971 version of this car, with a Massive 1192cc Mill. This brings me back. I don't recall the exact 0-60 time off-hand BUT it was somewhere in the 40's. At the time there was a joke about needing a Calendar. Please demonstrate the Spare Tire carrier. Coolest part of the car!
Agree with the pulley offset under load causing the belt wear. The side of the variable pulley that moves is the direction the arrow on the belt should be pointing. Next install put both variable pulleys on the same side. Of the engine, facing the same way. Use a shaft to transfer the driveshaft to the other end of your motor. Mount the variable pully on the end. Turn your engine around. Now both drive and driven pulleys have their squash plates facing the same direction.
The fact that MEH bothers people means you should say it more. Lol People can be so petty 😅 Awesome work as always man. Always looking forward to your Sunday uploads!
Your driven pulley is backwards, and yes I know you said that according to the instructions it is correct. I have a good bit of experience with CVT belt drive units on gocarts and snowmobiles, and while all I can do is offer my input I feel that it's something you should consider. The alignment of the belt should always stay perpendicular to the unmoving side of both drive and driven pulley. With all belt drive assemblies, misalignment at any point in the belt travel is the single most damaging variable.
Good catch on the spacing. Clearly you’re getting belt slippage at full CVT action. I question your obsession with the wide band readings. There’s an old saying from motorcycle customization, install an oil pressure gauge and that’s all the rider will be concerned about. Same goes for relying upon one single data input. In this case I’d be definitely tuning by ear and engine temp, specifically exhaust temp and spark plug reading. As for “meh,” another old saying comes to mind: less is more.
Yes 'meh' is meant to be written, not spoken. The other word, on the other hand, has even less appeal to a broad audience. Just sayin'. One change at a time keeps the variables to a minimum.
Fun and informative, again. People forget that this is just for fun ? I mean, if they are so bothered, they could go invest their own time, energy and money in to what they consider the "right" way to assemble or build their own whoopty doodle. 🤷♂️
So ages ago a friend and I were tinkering with an old 2 cycle MoPed, a Cimatti with a Minerli V1. We found a HUGE increase in torque with stronger ignition, ran a VW 1600cc ignition coil on it and gapped the plugs from about 15-20 thou to around 40-45 thou. It was able to light the mixture even when we changed up to 75cc and a high compression head and were running about 14:1. It was hell to start but it had some good 0-20mph acceleration. So long story short, don't forget ignition. The stock ignition is probably so-so on that engine and you might find some cheap/easy gains with better/stronger ignition especially as you try to get more performance from it.
@@greatestevar Why would you think I'm lying? More spark length and duration lights off more AF mixture at higher engine speeds and higher compression more easily, especially on a 2 stroke. May not be as dramatic for a lower compression lower RPM engine like the 670 but a larger spark will definitely improve things. If it's as easy as swapping for a stronger coil and upping the plug gap it seems like a no-brainer to try out, especially if parts aren't very expensive or hard to swap. I don't specifically know how the ignition on the 670 works but there's probably CDI boxes with more aggressive timing curves available. That wasn't the case on our old 2 stroke, it had no advance mechanism that I can recall, other than setting timing a little ahead by shifting the points plate under the flywheel/fan. I'm many things, a liar I am not.
Nice work Jimbo. Thats cool how others can contribute to the projects\experimentes through 3d printing! It must be frustrating, but probably the best strategy, in regards to explaining the same things over and over to try and dodge unenlightened comments.
Interesting stuff as always. Problems just LOOVE to turn up even though you tried to plan and eliminate them from the start. Having the right tools to observe what's going on, vs just guessing is always a good thing. Hopefully the next phase of the project has more positive results.
Another great video, thanks for the early upload. Hey Jimbo, try out the organic supports setting for your 3d printer. I think they are great, and will save you a bucket of filament.
The belts will always scrub a little, the contact patch isn't constant due to the circumference of drive pulleys, the outer diameter is moving faster than the inner.
I think you should call this video "addressing the idiot replies in previous videos" because it certainly isn't about what it says it's about. Oh wait, does that make me the subject of the next video? 🤣 I appreciate the light-hearted approach and the fact this is really just for fun.
Can't believe robot cantina crew has to consider people liking him saying meh. You'll never please everyone. You shouldn't have to explain yourself yourself for everything. Just keep at it 👍
I don't have any idea what meh means but it's your video and if it makes you happy do it, but please tell me what it means. I thoroughly enjoy your videos there is nothing else quite like them and i certainly appreciate the effort that goes into them. my mother bought a renault R8 to learn to drive when she was in her fifties, that was about fifty years ago I was only brave enough to go out with her once but the car was pretty good.
So, I suggest a Solar T-62T32 GPU Turboshaft Engine. It has a Gear Reduction down to 6000rpm from roughly 60000 and a rated Power Output of 150hp. As it operates at constant rpm it does have very good throttle response and very smooth power delivery thanks to the free spinning turbine. Since it doesn't require a clutch at all, the CVT could be done away with altogether. And given proper filtration, it is a true Multifuel Motor. You can find them in the US as Military surplus.
watching your cvt issues reminds me of when i was trying to tune the dual cvt system on my 81 honda express sr. ahhh the good ole days of getting stranded on the side of the road when the belt explodes lol
If you put a car starter motor and flywheel on the drive system to take off it would increase efficiency and make the car significantly faster and you would have the only 2 cylinder hybrid Renault. I've had the clutch cable break on a 2000 mustang V6 and the car would take off with the starter motor turning the engine and pushing a heavy car significantly faster than the 190HP motor in first gear but you probably wouldn't want to use first gear on that transmission because it would likely be too much torque.
MEH sounds OK to me! It's kinda like the "knights" who say "NE" Monty Python, you know 😂 Just Keep making your videos and experimenting. I do so anticipate each weeks' installment of Robot Cantina. Its a great break from the humdrum to totally negative videos I usually watch.
Love this type of stuff! watch the Saturn stuff (also great!) have not worked on cars for about 20 years... but this is some sort of ASMR... Maybe you already have done this, but when you have taken this project to the end maybe do guzzling V8 with EFI, ECU and make it as fuel efficient as possible? a sort of detune type of thing? see how much can be done with a older V8 (but still EFI, ECU one) and what you could do with it... Maybe do a "Freevalve" conversion? I mean with a custom ECU you could have it run on a single/dual cylinder on motorway for example... or have MPG mode/switch which does detune, and have all the creative ways for saving gas (custom stop/start thing) and a switch which is "race mode" and tunes everything up for that 0-60 :-) then you could sell kits :-)
I've always enjoyed your videos, from the first Honda Insight 212 swap video, I would say make them how you want to make them and ignore people telling you how they would make your video. As far as engines, if you get to motorcycles,my suggestion would be instead of the traditional RU-vid Hayabusa swap do like an old Harley pan or knucklehead or something like that! Love the videos as always Team RC!
I am not mechanically inclined in the slightest, but I really enjoy watching those at are. My all thumbs brain is actually "learning" things watching these (or I could just have a headache). As regards the "MEH"? I love it, it really seems to be targeting the basement dwellers so keep it up and re-double your efforts... or Meh.
During heavy acceleration, if possible, adjust the A/F MIXTURE ato 12.5:1. Also, it will help to install an offset key in the flywheel in order to advance the timing two or three degrees.
The belt might be non directional, but you are supposed to put it on with the arrow forward to keep it uniform and so you don't have to think about it when servicing. If it's worn in and you install the belt backwards it can cause thread pulling issues.
Things that could potentially help the 40 series torque converter has a (red spring) that’s adjustable one for off-road racing and inbetween there normally set at inbetween you simply just move the spring to either slot to adjust it change the gearbox oil for smoother shifting you can make your own short shifter by extending the shift linkage below the pivot if the shift linkage has any spongy rubber for bushings reinforce them with tiger seal or u can replace the whole mount with it this will act like a hard polyurethane bush idk if they sell upgraded roller weights and springs for the 40 series but that can also have a drastic change to how the car accelerates hope that helps with your build I very much enjoy this series and inspires me to build my own keep up the good work
This is very interesting to watch, you have new problems pop up, and then ways to fix. Personally I don't care about the "meh " or not. If you want to go ahead, if not that's ok too. 😊
Meh. Loved it. Glad you found the source, or so you think and fixed. Don’t agree with swapping parts or rebuilding stuff when the issue isn’t resolved. Bring it up 1/4 in and test. Keep the meh comin sir.
People who count the times you say mah are not paying enough attention to the riveting high performance content of you videos. Say it as much as you like.
Comet Duster clutches were popular on snowmobiles back in the day. Had a late 70s Arctic Cat that had one on it. Would be an expensive upgrade but would hold up to the abuse your showing it. Just something to keep in mind for future modifications/projects. Snowmobile motor and clutch setup would be a great power plant for a future project.
My two cents, the carburetor works fine but it's finicky depends also of humidity on the air, if it's cold or hot, and the altitude...with the dual carburetor setup you will get an slightly better throttle response but you will have to compensate for the lack of air boxes, too much work looks better, I prefer to keep it simple, that 36mm it's the best match for that engine, love your catch frase "but that's an experiment for another day and not too shabby!!!. I like to learn from you and my daily job as motorcycle technician
Just a ?. I need a little advice. I got a shaft driven motorcycle engine I want to mount on a go-kart frame. Any idea where I could find a shaft-to-chain conversion kit?
I'm going to tag along here with Alex, since my tuning background centers on motorcycles. Alex covers a lot that I agree with .... in addition, you are only getting an AFR from the "average" of both cylinders. Best case is that the cylinders and close, making the AFR close. However, it worries me that in an previous episode you run "pig rich" and all seemed good. That easily could mean you really have an inbalance in the cylinders. You really, really need to run 2 WBO2 sensors.
@@mathewbryant1921 that's a tough one, as far I know there isn't a direct conversion for that appliance, need to key the output shaft from the engine and try a secondary transmission like a Harley Davidson, but it's bulkier, a direct gear chain sprocket to a driven gear will be to harsh on the output shaft as you telling it's directly the crankshaft, that's my humble opinion.
@@Alex_Miller1980 so what about shortening the driveshaft from the bike and using a side by side rear diff? I mean I know the measurements have to be exact for the universal joint to be usable as is, but I'm quite capable. Just trying to gather all the pieces before I really get started.
Thanks! The 36mm carb is probably the best for a simple modification on this two cylinder engine, but we will also try the difficult to setup twin carbs just for fun. It will be interesting.
As for the "Meh" thing ... I'm not exactly a fan, but if it pisses people off, I say keep doing it! After all, isn't that what the internet is for -- pissing everyone off?!?
Great video .I think your problem with belt wear is your pulleys.the clutch and variator clutch none moving side should be on the same side which makes it straight at all times,makes even friction less belt jump. the other way opposite will never be center.
off topic for this video but i just wanted to let you to you know : Honda insight is over here in the netherlands often seen so i figured that parts are also available.
Maybe the arrow on the belt is to make sure you install it in the right "radial direction", i.e. turning the right way because the *structure* in the belt is actually directional? Like on some tires (meant to be installed one way on the rear to transmit power and the opposite in the front to transmit braking force). Or maybe because people are used to have arrow on non-symmetrical belts and they complain when there isn't one?
4:08 I got it. From Gumball Rally. Quotes. Franco : And now my friend, the first-a rule of Italian driving. Franco : What's-a behind me is not important.
