3 pounds off the flywheel is HUGE. Rule of thumb is every pound of rotating weight you can remove from anywhere in the powertrain is equivalent to removing 6 pounds of dead weight from the motorcycle. A 9 pound flywheel is really heavy to start with so taking 3 pounds off it is not excessive at all. Excellent work.

Im a cnc machinist and have learned a lot from you. Awesome videos

Adam I had a shaft at work about a year ago that i machined over a hundred pounds off of it. I knew there would be a lot of machining, so i couldnt resist weighing it. That was a fun job cleaning out the chip pan for that one. I agree with Bill and Tom for that matter. Ever since Tom suggested buying a composition book and jotting down notes, i have filled pages upon pages with different things i do in the shop. Everything from fixtures for repetitive work to how i do things that come along once a year. Great video, that material finished better than it was from the factory. Mark

Adam you are a one hit wonder. I wish I could tap a part in my chuck which is one thou out and with just one tap get it true. You are a master machinist and a great mentor to all the newbies who rely on KZfaq to learn our craft, keep up the good work and thank you!

Adam, As always, another great video! It's great to see you back in the shop and doing what you love to do. Thanks again. Dave

As someone who hasn't done any machining except for high-school thirty years ago, I just want to say I love watching you, Tom, Keith and all the other KZfaq machinists at work - the best "Reality TV" there is - and your "toys" make me envious. Thanks for sharing, guys.

Adam.. 6 years!! I really hope you occasionally look back at your library of videos. EVERYTHING has progressed in such a positive way. You, you're shop, the videos them selves.. You're killing bud!

Love watching you work . My father had a sheet metal factory, when I was young I enjoyed going and watching the men work . Your attention to detail is amazing. Thanks for making the videos.

This is my favorite content right now. So happy to see such skill and knowledge put to work and the generosity of sharing this with everyone.

Adam, thanks for the vid. Always interesting to see a pro at work. On the clutch question, motorcycles typically have a multi-disk wet clutch (in oil), not a dry friction plate against a flywheel like in a car. Slipping the clutch in a car will burn up the clutch in a hurry, but on a bike that's a normal part of riding at slow speeds, such as making turns in parking lots. The multi disk clutch has alternating friction and steel rings that bear on each other, not on a housing or flywheel. One set of rings is toothed on the OD, and the other is toothed on the ID...clamping them together transfers power. I suspect that the magnet has to do with sensing RPM or crank angle for an ECU to use for controlling timing. -- Mike

Great video again. I used to do that on 2 cycle dirt bikes back it the 70's. It made them rev to max fast as an electric motor but it also took away most of what little low end torque they had and 2 cycles don't have much low end torque. They had to keep the revs up. It was a fad and most dirt bike fads back then tended to last about 90 days. Keep up the good videos.

Very good work, a real craftsman!!! We do not have enough man like u.

Hi Adam, You can tell you have done several of these flywheels. Good to see you back. Keep up the GREAT work! Take Care, Reid

I enjoy watching your videos, I always learn something interesting. I'm sure your customers are always pleased with your professional work. Job well done .

its great to see you back in the shop Abom!

Thanks for sharing Adam. We've been doing this to ATV's for quite a few years. It makes the bikes rev super quick but they stall a lot easier with less momentum. Andy Maul

Great video Adam-Glad your back in action. Cheers

It would be cool to have a junk one, so you could slice it in half, and really see what you could work with. Great job Adam !!

Always interesting! Thanks Adam, you rock...

great job ! I think many people who have never raced bikes missed a point that you are an important STEP in bike tuning and it is 99.999% certain that the flywheel will be off for race balancing as the NEXT step along with the probable new cams and crank (which again will be lightened first) it was great to see as always Personally having had many bikes over many years I at least saw that because of the STAGE the tuning process was at a 4 jaw makes no real difference as long as structure is maintained and as always you excelled best wishes

Nice work as usual. You deserve the good comments and I'm sure you've noticed that praise comes not just from guys like me that are beginners, but from top professionals out there. Acknowledgement from those who have achieved excellence has got to be encouraging. Thanks for sharing; keeps the light lit.

Great job on that flywheel, Adam. Nice to have you back! :)

Not only do you need the right equipment, it's your knowledge and experience that makes the difference.

This video is pretty well aged now but very useful. Have always had this mod done on my race bikes. Excited that now I finally have a lathe of my own I can have a shot at doing it myself.

Wow nice work adam that is a crazy amount of weight loss on a fly wheel..And as you know the performance gain from taking that amount of weight off the flywheel incredible..Thank's..Hope all's well mate..

nice to see you back Adam, keep your head up for your family, :) another nice video "THANK-YOU" regards keith Swindon uk

Awesome job Adam. I'm a bike rider myself and I know how much a lighter flywheel gives to the engine in terms of "readiness". Thumbs up :)

Nice video, you made it very clear to understand, so all of us can learn from it.Thanks.

This is how I would envision a production machinest to do it. You are fast and accurate - I'd love to send you my projects :P

Another great video. Nothing like seeing U Dudes at it. Much appreciated as well. aRM

GREAT TO SEE YOU BACK.

Enjoyed the video. Thanks for sharing!

The speed and efficiency you do these jobs just blows my mind. The quality is just is fantastic. Someday I hope I can do this quality of work.

I like the way your machines are cleaned foe next job .. very professional

Great Video ! Love your work.

nice work as usual ... thanks for the video.

Nice work Adam, I used to do that on automotive flywheels for local drag racers down in Gainesville... You've got to wind her up and dump the clutch, but they had plenty of power to light up the tires coming off the line! Thanks for sharing this! :o] O,

Hey Adam love your videos keep them coming

its going to rev some with the flywheel being three llb lighter i remember getting my mini flywheel lightened it use to rev like formula 1 car lol good video adam

keep up the good work. love your videos

Hi Adam Nice job The lighter fly wheel gives a better (faster) pick up The way you had it mounted (running true) the balance should not be a issue Regards John

Fun to watch you work...

I,am sure the people at the Triumph shop know first hand why they want you to do what you do something is working. Less weight faster bike, Could be wrong, And i could be right. Nice job Adam. I love Triumph,s cook it up.

Nice job Adam,

Another great video Adam, that Iscar insert does a beautiful job. By the way who won the face off, that was fun watching.

Great video, enjoyed it.

I'm just curious Adam...and I sure hope I don't touch upon a sore spot. I'm sure you know just how much everyone who is worth a damn loves your videos, shucks, we even love you personally! With that said, who in the heck gives a thumbs down on a nice and mellow video like this? You share your time and effort and show people a few things along the way, so I don't understand the negativity? I know, and am proud of the fact, that we live in a free country where you can express your opinions without fear of repercussion, but I guess I will never understand a person going out of their way to knock someone's efforts at goodwill and sharing when they can just move along. Why not just go on your way and watch something else? Huh...I'm sorry to bring up the lonely little hater and his one tiny thumbs down. Like I said in the beginning, I'm sure you know the people that matter think very highly of you. You are one heck of a nice and intelligent guy! Just poking through your archives looking for some shots of tool angles to try and figure out what I'm doing wrong when I saw the blemish. Nothing a little emery cloth won't polish away, he he. Aloha...Chuck.

I really appreciate the lesson and video. Thank you.

Good show Adam!

Thank you for making videos!

Hey Adam, Finish looks great even with those holes in the part, What is the Iscar insert CNMG??. Nice job, I'm sure the owner will be noticing three pounds off his rotating mass. Talk to you soon. Tom

Nice and good workmanship liked it very much.

Great video man. Thanks.

Looks great. That is a very interesting vintage tool post. Never saw one like it before.

Your nickname is now "Quick Draw McGraw" for the fasted setter upper. One hit with the homemade lead hammer and "BAM" quick draw gets er done. I know that's Keiths little saying but it fits here as well.

Something to remember when my hubby installs his custom 80cc 2 stroke on my beach bike

That is a heavy ass flywheel! Damn.... 9 lbs!

You are doing good Adam.

After watching your videos i want to make some precision work to! hahaha! I have never used a lathe but i love watching u do. Such skilles i would loved to be ur customer :)

Very late comment, kinda catching up. Lovely work. This is 4 years later so hope it is stil working well and the rider is safe. Have a Honda myself. Ty.

I like the work you do and the meticulous explanations and demos that accompany them. I noticed a few dimples on the face of this flywheel. I suppose these were used for balancing the flywheel. These were taken off when you gave turned the fly wheel. Would this flywheel have to be rebalanced?

Totally rad!

Nice mod and thanks for the video

you do fine work

You ara teaching turning us. Thank you very much.

Thanks heaps Adam.i just bought a new hobby mans 5inch lathe and all your experience and technology is most helpful. I'm a retired motor mechanic so have your tips to learn from. Thanks again.

nice work bro

Don't they need to be balanced again after you've taken off a lot of the balancing holes and changed the geometry? And wouldn't it be better to finish those steps with a radius fillet for strength?

Ppl commenting about the balancing after turning. I've often found that a lightened flywheel thats been turned on a lathe will be pretty balanced. Especially on cast flywheels. You can see how out of true it was when Adam touched off the face of the flywheel and the outer radius. Turning it centered and square in the lathe will improve the balance.

Nice work Adam, I'm going to have to look how that flywheel is used in the Triumph. Do yourself a favor and make up a little sketch and throw it in a binder. That binder will be very useful in 10 years.

good to see ya bud

I'm also interested in the effect (if any) on balance. Obviously since this is coupled straight to the crankshaft, it might not be easy to notice but I imagine that it's just a little bit more strain on the bearings. I'd be curious to see it mounted on those shaft inspection rollers you showed us a while back.

Nice work there Adam. My instructor said you were really good. He's right, Jim

The weight of the wheel is critical to what they want the engine to do. Did they experiment with different weights to get the desired results? I guess what I am asking is how did you come up with the formula for the first one? I would figure it was something somebody else did and gave a desired weight to end up at. Keep doing your thing Adam! Single life is best.

Very cool Adam, you're probably sick and tired of being asked the balancing question and I read a lot of the comments in this video and your patient repeated answer "The balancing is handled by the bike shop" but you showed us your persicion toller jig to check the balance and trueness of a shaft a few weeks ago, are you not curious about using it to check the balancing? I know I am and the bonus would be we get to see that tool in pratical use! One last question, I've started to watch videos and read the interweeb on identifying alloys, you mention that this metal is pretty hard (and it sure does look like it in the video). Any pointers how you would go about determining the alloy of that flywheel? Not looking at the actual alloy but the process you would use to determine it. Curious mind want to know. As always, we are very fortunate that you take the time to PRODUCE these videos. Filming the job is the easy part, you must spend ridiculous time on post production - THANKS for that. Take care from Cold Canada where it's -10°F and getting another foot of snow tomorrow.

I know this is an older vid but im curious as to the loss of balance due to the balance drillings being machined away?

Cute little thing lol..I used to mill and balance CAT flywheels damn things were near 100lbs. We did flywheels for all different companies id run about 110 parts in 10hrs first mill then balance then stamp and pack in shipping crates on a pallet. Was kinda a fun job to be honest depending on what lathe operator I worked with, hated the lazy ones makes the night drag. Made a lot of friends and a lot of parts

Nice! 👏🏻👏🏻👏🏻👏🏻👏🏻👏🏻🌸

You certainly met the customer's specification regarding weight reduction, but what about balance? Motorcycles typically run at high RPM, and leaving the flywheel even a tiny bit out of balance could significantly decrease the engine's performance and lifetime.Does the customer rebalance the flywheels after he gets them back from you, or is it something that was never addressed?

Adam, First, thank you for making these video's. I have watched quite a few of your videos now and find them informative and entertaining. Between yourself, Keith F, Keith R, Doubleboost, mrpete222 and one or two others, I don't think I'll ever have to watch TV again! One question on this video though. I note you don't ever use carriage or cross slide stops. I would have thought on a job like this flywheel, it would be ideal to use stops so you can come up to exactly the same point for each cut (which you do with your mag-base dial gauge). Is this personal preference, or is there a technical reason for this? Cheers, Brad

I have been thinking about getting a lathe to tinker with and found this video highly informative. I have an old honda CB 550 and am wondering if this mod would help save fuel, as in mpg. Thanks for the post Adam.

nice cool can you do all the milling for creating crankshafts , camshafts , pistons , and valves as well as all the rest of the internal components of engines and transmissions

Just like Butta!

Good job.

3 lb doesn't sound like much, but the further out it sits on the work piece - the more effect it has in reducing this thing's moment of inertia (which is what we want) so I'd say that's pretty awesome! Before starting on this though I'd ask the customer about any load bearing features on the item and treat them very gently, and with massive radii nearby to prevent fatigue cracks. I'm guessing however that anything that takes any actual load is on the inner side of the flywheel, those fingers look like they could be clutch engagement, but they're spaced far too irregularly for that, so my guess would be they work with a Hall effect sensor for engine timing

hi adam, do you not lubricate on anything, like a philosophy or somthin´like that ... ?!? great work (this is my 3rd. video), by the way. i´ve learned so much from you already , thanks ever so much for all that information ! cant wait to see the next one...greetings from a limey livin´ in germany. ..alan

Adam, I like the set up on the lathe with the extra support from the center. Youmentioned the use of the carbide insert. Is the flywheel too hard to be cut with a HSS tool? Thanks for posting a nice clear video. Regards, Eric

Another great video, thanks Adam What kind of maintenance do you have to do on your 3 & 4 jaw chucks. Is their a routine maintenance schedule for these, or do you run em till they drop & then rebuild or just plain replace?

surprised you didn't do any stress relief radius since it was a flywheel and all

The most effective way to reduce inertia in a flywheel is by removing mass further away from the center axis. Of course, don’t make it too thin anywhere.

4:00 - This bloke is good!

Damn I misread and thought it was going to make lightning... Very disappoint.

Nice Job, what camera are you using ? Clean clear and the audio is nice !

Hey Adam, Why not use a expanding mandrel or make one and turn between centers?

That's quick work but nice bread and butter stuff for you. :-)

Nice work but how do you rebalance it?

I am kind of surprised you did not fab up a stub arbor with a threaded center hole & flat washer & bolt the same size as the crank to hold concentrically to the center of the crank. Also since you cut all the balance holes out, how did you rebalance it ? I use balancing wheels when doing racing outboard flywheels Adam . ------> FLYWHEEL BALANCING: The first thing I do is make up a stub shaft to mount the wheel in the lathe. This is done as follows, a piece of stock with a bigger OD then crankshaft is installed in the three jaw chuck face and center drilled for a live center. Set the compound of the lathe so that it will cut the same angle taper with the compound of the lathe as is on the crank if it is a tapered crank, cut the taper down until your live center just touches its mating center hole and will allow you to lock the flywheel on the taper you cut with the compound. Try and keep the shaft short as possible so the flywheel clears the chuck of the lathe. Take a dial indicator and rotate the shaft to check for run out of stub shaft. There must be no run out. Mount the flywheel on the fabricated shaft and lock with the live center on flywheel tight. Check the O.D. of the wheel. My wheel was .030 out of round. A total of .070 was taken off the O.D., .035 off each side to clean up. More can be removed if wanted . After machining re balance turned flywheel on static balance wheels and drill lighting holes as needed to bring in zero spine roll back of flywheel on wheels. -------> cdn1.bigcommerce.com/n-yp39j5/4s9liwcv/products/117156/images/297507/WBS-002__49754.1462909489.1280.1280.jpg?c=2

Hello There, I am one of your subscribers (from Norway) and really enjoy watching your vids. They contain a lot of "learning material" and your style of explaining jobs & procedures is very helpful for a hobby machinist like myself. On your video here, as on others, you use the dial indicator with a magnet fixed to the back. Is this a shop mod on a regulator indicator or bought as is? I am contemplating purchasing a DRO, you see (yes, into the discussion on glass scales vs. magnetic etc. etc.), but this way of using the indicator seems to almost do away with a need for a digital read outs for short workpieces. Or am missing something? Also, the ball joint indicator mount looks like having a one screw fixing point, correct? You make it all look like easy as h.. but this device shure looks like a timne saver.. There are now some very good channels to follow, eg. Mr. Fenner's and other pro's that take their time to share knowledge... Much appreciated, keep up the good work!

It appears that there is some balancing drilling done on the stock flywheel (rotor). Does the lightened flywheel get dynamically balanced by someone else or is there no need for it?

What brand of calipers are you using in the video? Also have you done any CNC work?