Great one Dale: Back in the 70's I was hanging around a tool and die makers shop that did the factory service work for Montesa Motors and Cooper Motors. The only lathe he had at the time was South Bend 10 Heavy. He did all his cylinder boring With a small Van Norman boring bar on a 2-inch surface ground plate with a hole in the middle, mounted on a plastic milk crate. Things got better as time passed, and he even built a water brake and flow bench. I even got to meet the Super Hunky.
Hi Dale, The RM Suzuki is what I first loved as a teenage boy in the 80’s. I remember a guy at school talk about a RM 125 he had, he said it had so much power that it would rip the knobs the tyre. Wow I thought, I need to get me a RM. This started my love of motocross bikes for decades. The RM is my favourite project of yours so far, I really enjoyed this video, thanks for all the extra work you do in getting the great footage as your doing the repairs. I also appreciate you explaining as you go what your doing. I love the talk you give at the end of your videos as well. Cheers
Hey, thank you very much, I love the RM125 story, think we all may have a similar story, but what it boils down to is the love of the old bikes, and the great times we had growing up with them. You are too kind, and I have to tell you that the RM250 is also my favorite series to date also. Really enjoying bringing this one back to life. I am trying to learn more about the camera, the one issue I have is it doesn't do close up well, I have to remember to use my phone camera for the close-up work, it is much better. Thanks again for spending time with me in the shop.
Welder, lathe and mill ... yup, that checks all the boxes! Another great video on how to repair an item with the tools and knowledge that you have. Bravo for getting the job done. I have only been a subscriber for about 6 months and I learn something from each of your installments. I hope that you continue posting videos for many years to come.
Thanks Dan, this is a lot of fun for me. I enjoy the bikes, but the machine work is great. I like to mix the two together to show what actually happens when you drop off your part at the bike, or machine shop.
Awesome work on this cylinder- subscribed and looking forward to more videos. I think you approached this in the best way possible given the overall condition of the cylinder. When the deck height is incorrect or if there is bad pitting I'll opt to weld the entire surface, but its slow going and requires boring in addition to decking as a result of heat distortion. I've used millennium tech for their nikasil coatings and I know they offer this type of work as well. As time goes on it gets harder and harder to find replacements- heck- that's the premise to my entire business. I did a lot of repair work like this to my 93 RMX250 - welding and machining the clutch basket for example- due to lack of parts availability. If you come across anything that requires 3D Scanning, CNC work, etc, reach out- I could see it making a cool crossover video.
Hey Dave, sounds like you have been in the thick of things a few times. Man, it would worry me to weld the entire surface up. You're a better man than me. You are right though, more and more of these parts are needing more and more work to make them serviceable again. It is hard to convince many folks that all that work is necessary. I am open to a crossover video, but I know nothing about 3d scanning or cnc. I barely get loading videos to youtube. But will keep it in mind, and I thank you. Thank you again for the sub and for hanging out in the shop with me.
@@montana2strokeracer I have to agree with you on that! Still looking for that one CR250M. I also need to finish up a few projects on the computer. The structural drawings and Lateral analysis for these take a bit to get through.
Wow.....thanks Bill, they were a bit more machine shop stuff, I am seeing a trend leaning more toward machine shop stuff for these bikes. But have to also keep the folks happy that just need to repair their bikes. I think most folks really didn't know what happened to their parts after they dropped them off at the bike or machine shop. All you normally see is the finished product. Think a lot are enjoying seeing what actually happens.
@@montana2strokeracer yes sir there's a lot more to it then most people know. I've run into that problem my self restoring theses old bike. Dealing with a cyclinder problem on my 1976 Suzuki rm125 a model. A one year only. But anyway keep up the good work and sharing with us. I appreciate your time and knowledge. Thank you so Dale.🏁👍💯
Thanks, Murr, I am learning, the gopro just doesn't do close ups and sometimes I forget. I need to pull my phone camera out when I do them. Small steps.
Thanks for Your videos. I am just learning how to use My metalworking lathe and it's good for Me to watch things be done. I can get the sense and feel when I'm watching You work. I have a smaller lathe it's a Portass model S from the 1950s' that I am restoring and upgrading as and when I can. I have some feel for turning metal as I have come from a woodworking background and have done piecework turning as My first job back in the 70s' Best Wishes Jahmahrah
Hi Jahmahrah, that is great, you are going to love working with your lathe, all the parts that you can repair or make is amazing. Glad to see you may be picking up some pointers from my channel. Thanks for watching and hope you check back often.
Great job Dale! In the last video you listed the countries that watch you... So I’m from Russia and I watch you with great pleasure! Be healthy and good luck in all your projects. I’m really looking forward to episodes that are just as detailed on RM. Best regards, Dmitry!
Hi Dmitry and welcome, hope you are doing well my friend, I worry about the part of the world you are in. I pray for peace. Sure, glad to have you joining me in the shop to work on old motorcycles. The RM episodes are really fun and have a special place in my heart growing up.
Nice repairs! All of those ports look pretty rough, I must admit that I'm not sure that I could not resist at least cleaning up the inlet and exhaust tracks, they don't even look round to me! I also understand why you are not doing that sort of stuff at this time, I guess you have more than enough other things to fix first!
Thank you, oh I probably will at some point do a cleanup, but this bike will be more than I can handle in stock form. If I make it too fast, I will just end up breaking my 70-year-old bones. LOL
I have seen similar damage on cilinders "mechanics" ( or "panics" ) using a chisel in between mating surfaces to remove a cilinder from the crankcase being the cause. To repair in a lathe I use a mandrel which I bring to size in situ in the lathe and without removing the mandrel I slide the cilinder over and use one of the head bolts to secure it to a welded on bracket
Yes, it's pretty wild what folks do. I am sure the mandrel would be the right way to do it. But I don't have any, I am not a Job Shop, just a hobby guy, I wish I had some mandrels but have not run across any reasonable priced ones. I am looking for some.
Hi Dale, Nice job. I really am going to have to dig out the 82 YZ250 I've had sitting in shed last 10~15 years. (although I've been saying that for 10~15 years 🤣) For a non machinist, you sure do have a lot of machine tools 😎 When you were smoothing off the base with file I was thinking 'I wouldn't be able to resist cleaning up those ports and re-profiling entry to transfers properly'. Someone has been in there in the past, Suzuki made things a bit more even, looks like it was filed? It's been a long time since I did an RM 250 (around 1985~86), matching transfer to case and re-shaping reed block. Quite envious of @johnyoung3103, Super Hunky was a great writer in his various 'disguises' in Dirt Bike. Was saddened to hear he passed away last year
Thank you, go ahead pull that puppy out, and bring it back to riding status again. I too am envious of John's memory of meeting Super Hunky, I still have the first issue of Dirt Bike magazine, and many others, and his column was always full of good info and humor. Great man, and he will be missed.
Hey Mark, man that JB weld gets a bad rap sometimes, it is very useful in many ways. I actually thought it would be just as good a welding this at the base anyway. Just sided on the more permanent repair instead.
Yeah, it always takes more weld than you think. It'll be fine. I mill a lot of aluminum, and use a much higher speed. Are you really sure that's an RM cylinder and not a PE? I can measure the exhaust port height on mine for you if you want to find out for sure... Nice video, as always, Robert
Hey Robert, yes absolutely sure it is RM, the PE exhaust ports are about .095 lower. This is a 1978.5 cylinder; you probably saw the rubber insulators. On the PE they go in the vertical gaps on the fins, these go horizontally between fins. Not all RMs got insulators, only a few in 78.5 model change. The 76 cylinder is a completely different bore at 70mm, and it has the vertical slots between the fins, the 77 through 78.5 have 67mm bore 70mm stroke, the 77 and 78 has no vertical slots, the 78.5 has the return of the vertical slots and some got the round rubber insulators between the fins. Also, some porting up grades.
Hi there, you know I really didn't consider using a bull nose center. I guess I did not think there was enough stick out to warrant it. Some others have said that it can put too much pressure on the bottom of the sleeve and break an ear off. I don't know that firsthand though. I think if you were cutting further out you may need to stabilize it somehow, may be with an expanding mandrel or something to that effect.
Hi there, in the 70's-time frame I would have to say the Suzuki's were more durable. There were a lot more Yamaha's made though. So, lot more parts, new and used out there. Just my opinion of course.
Hi Jim, that would be nice but not necessary and it causes other problems. I briefly covered that in the video. But it would have probably taken .020 to clean it up, then that brings your ports down .020, so you would have to go back in and raise all the ports the .020. Then since the rod is going up toward the head .020 more, you would need to recut the head to remove .020 so the compression wouldn't be too high, and the squish area in the head would need recutting also to prevent pre ignition. So, you can see by changing one thing it is just a snowball effect that just has too many other consequences. Good question though. Thanks for spending time with me in the shop.
Great one Dale: Back in the 70's I was hanging around a tool and die makers shop that did the factory service work for Montesa Motors and Cooper Motors. The only lathe he had at the time was South Bend 10 Heavy. He did all his cylinder boring With a small Van Norman boring bar on a 2-inch surface ground plate with a hole in the middle, mounted on a plastic milk crate. Things got better as time passed, and he even built a water brake and flow bench. I even got to meet the Super Hunky.
Thanks John, what a cool story, and to meet the Hunk.....fantastic!
Hi Dale,
The RM Suzuki is what I first loved as a teenage boy in the 80’s.
I remember a guy at school talk about a RM 125 he had, he said it had so much power that it would rip the knobs the tyre.
Wow I thought, I need to get me a RM.
This started my love of motocross bikes for decades.
The RM is my favourite project of yours so far, I really enjoyed this video, thanks for all the extra work you do in getting the great footage as your doing the repairs. I also appreciate you explaining as you go what your doing.
I love the talk you give at the end of your videos as well.
Cheers
Hey, thank you very much, I love the RM125 story, think we all may have a similar story, but what it boils down to is the love of the old bikes, and the great times we had growing up with them. You are too kind, and I have to tell you that the RM250 is also my favorite series to date also. Really enjoying bringing this one back to life. I am trying to learn more about the camera, the one issue I have is it doesn't do close up well, I have to remember to use my phone camera for the close-up work, it is much better. Thanks again for spending time with me in the shop.
You really take good care of your motors 😊
Thank you very much, sure appreciate you taking the time to watch the video.
great job as always dale should seal up fine keep up the great work next video please
I think so too Mark, thanks for stopping by, sure appreciate it.
Getting it done without messing up = machinist. Another great set-up on the mill Dale
Ha, ha, ha, thanks Gary, I really do need to set down and learn bolt circles. I am going to make that a future video. Thanks for all the help.
Great. Looking forward to that future video. I sent you a reply on the previous video regarding alum. soft jaws for your 3 jaw lathe chuck.
Got it, thanks
Welder, lathe and mill ... yup, that checks all the boxes! Another great video on how to repair an item with the tools and knowledge that you have. Bravo for getting the job done. I have only been a subscriber for about 6 months and I learn something from each of your installments. I hope that you continue posting videos for many years to come.
Thank you, Pete, and thanks for your subscription, I am enjoying this TH-cam thing, it sure keeps me busy in retirement and I like that.
Super work Dale. I've been tuning in for a couple of years now and you are stuck with me I'm afraid. Best wishes, Dean.
Oh, gee whiz Dean, sure appreciate you enduring all those terrible videos. You're a good mate, my friend.
A most impressive repair and restoration. Well beyond a bore job. You are indeed a machinist! 2 thumbs up!
Thanks Jim, still got the boring to do. Lots more to do on the RM250
Fantastic work as usual Dale. It’s obvious you enjoy this work, and I do too. See you next video.
Dan
Thanks Dan, this is a lot of fun for me. I enjoy the bikes, but the machine work is great. I like to mix the two together to show what actually happens when you drop off your part at the bike, or machine shop.
Awesome work on this cylinder- subscribed and looking forward to more videos. I think you approached this in the best way possible given the overall condition of the cylinder. When the deck height is incorrect or if there is bad pitting I'll opt to weld the entire surface, but its slow going and requires boring in addition to decking as a result of heat distortion. I've used millennium tech for their nikasil coatings and I know they offer this type of work as well. As time goes on it gets harder and harder to find replacements- heck- that's the premise to my entire business. I did a lot of repair work like this to my 93 RMX250 - welding and machining the clutch basket for example- due to lack of parts availability. If you come across anything that requires 3D Scanning, CNC work, etc, reach out- I could see it making a cool crossover video.
Hey Dave, sounds like you have been in the thick of things a few times. Man, it would worry me to weld the entire surface up. You're a better man than me. You are right though, more and more of these parts are needing more and more work to make them serviceable again. It is hard to convince many folks that all that work is necessary. I am open to a crossover video, but I know nothing about 3d scanning or cnc. I barely get loading videos to youtube. But will keep it in mind, and I thank you. Thank you again for the sub and for hanging out in the shop with me.
As always, nice work there Dale!
Thanks Dave, what no new bikes following you home today?
@@montana2strokeracer I have my hands full with the ones I have. Still trying to get the 71 TM's back together and waiting on some parts.
I know Dave, but I still bring more home, it's a sickness I believe.
@@montana2strokeracer I have to agree with you on that! Still looking for that one CR250M. I also need to finish up a few projects on the computer. The structural drawings and Lateral analysis for these take a bit to get through.
Absolutely great work on that disgraceful barrel Dale. And don't underrate yourself mate. You're an excellent machinist by any measure.
Cheers, Peter.
Thanks Peter, man it was just about junk, I have three more cylinders that are nicer, but worn out inside.
Dale your videos are always entertaining , interesting and always informative !
Thank you, John, I am glad to hear that. It is my goal to inform and entertain.
Awesome work Dale. I love watching a Master at work!!!!
Thanks Don, what have you got planned for this week?
@@montana2strokeracer, I am picking up a 86 YZ 250 tomorrow.
Wow, you're going to have to build that new shop quick my friend.
Dale another great show. You knocked it out of the park on the last two shows. Great work.💯🏁👍
Wow.....thanks Bill, they were a bit more machine shop stuff, I am seeing a trend leaning more toward machine shop stuff for these bikes. But have to also keep the folks happy that just need to repair their bikes. I think most folks really didn't know what happened to their parts after they dropped them off at the bike or machine shop. All you normally see is the finished product. Think a lot are enjoying seeing what actually happens.
@@montana2strokeracer yes sir there's a lot more to it then most people know. I've run into that problem my self restoring theses old bike. Dealing with a cyclinder problem on my 1976 Suzuki rm125 a model. A one year only. But anyway keep up the good work and sharing with us. I appreciate your time and knowledge. Thank you so Dale.🏁👍💯
Thanks Dale , Really great camera shots and placement !
Thanks, Murr, I am learning, the gopro just doesn't do close ups and sometimes I forget. I need to pull my phone camera out when I do them. Small steps.
Great watching your machining artistry Dale. Super neat saving a cylinder like this.❤
Thank you, I try hard but am not a professional, I have to agree, these parts have to be saved.
Very good work. You’ll be happy with the performance of the bike later. My own C2 cylinder mildly ported , but Not base Milled.
Thanks James, and again thanks for all the great parts you sent my way. Hope I can do them justice polishing them up.
Another great video Sir, Wish we were closer because I have a GT-80 and a TC 90 I would love you to go through!
Thanks Mark, that would be fun for sure, I always enjoy bench racing with my buddies, that's half the fun you know!
Thanks for Your videos. I am just learning how to use My metalworking lathe and it's good for Me to watch things be done. I can get the sense and feel when I'm watching You work. I have a smaller lathe it's a Portass model S from the 1950s' that I am restoring and upgrading as and when I can. I have some feel for turning metal as I have come from a woodworking background and have done piecework turning as My first job back in the 70s' Best Wishes Jahmahrah
Hi Jahmahrah, that is great, you are going to love working with your lathe, all the parts that you can repair or make is amazing. Glad to see you may be picking up some pointers from my channel. Thanks for watching and hope you check back often.
Great job Dale! In the last video you listed the countries that watch you... So I’m from Russia and I watch you with great pleasure! Be healthy and good luck in all your projects. I’m really looking forward to episodes that are just as detailed on RM. Best regards, Dmitry!
Hi Dmitry and welcome, hope you are doing well my friend, I worry about the part of the world you are in. I pray for peace. Sure, glad to have you joining me in the shop to work on old motorcycles. The RM episodes are really fun and have a special place in my heart growing up.
Nice repairs! All of those ports look pretty rough, I must admit that I'm not sure that I could not resist at least cleaning up the inlet and exhaust tracks, they don't even look round to me! I also understand why you are not doing that sort of stuff at this time, I guess you have more than enough other things to fix first!
Thank you, oh I probably will at some point do a cleanup, but this bike will be more than I can handle in stock form. If I make it too fast, I will just end up breaking my 70-year-old bones. LOL
Great work Dale as always. I learn alot from you mate.
Thanks Nathan, I learn a lot from all the super folks out there, never too old to learn more stuff.
I have seen similar damage on cilinders "mechanics" ( or "panics" ) using a chisel in between mating surfaces to remove a cilinder from the crankcase being the cause. To repair in a lathe I use a mandrel which I bring to size in situ in the lathe and without removing the mandrel I slide the cilinder over and use one of the head bolts to secure it to a welded on bracket
Yes, it's pretty wild what folks do. I am sure the mandrel would be the right way to do it. But I don't have any, I am not a Job Shop, just a hobby guy, I wish I had some mandrels but have not run across any reasonable priced ones. I am looking for some.
Love the videos
Thank you, sir, appreciate you taking the time to hang out with me in the shop.
Hi Dale,
Nice job. I really am going to have to dig out the 82 YZ250 I've had sitting in shed last 10~15 years. (although I've been saying that for 10~15 years 🤣)
For a non machinist, you sure do have a lot of machine tools 😎
When you were smoothing off the base with file I was thinking 'I wouldn't be able to resist cleaning up those ports and re-profiling entry to transfers properly'. Someone has been in there in the past, Suzuki made things a bit more even, looks like it was filed?
It's been a long time since I did an RM 250 (around 1985~86), matching transfer to case and re-shaping reed block.
Quite envious of @johnyoung3103, Super Hunky was a great writer in his various 'disguises' in Dirt Bike.
Was saddened to hear he passed away last year
Thank you, go ahead pull that puppy out, and bring it back to riding status again. I too am envious of John's memory of meeting Super Hunky, I still have the first issue of Dirt Bike magazine, and many others, and his column was always full of good info and humor. Great man, and he will be missed.
Many thanks for uploading this
Thank you very much, hope you will join me often as I work in the shop.
Nice work Dale.
I just subscribed to your channel.
Have a great day.
Thanks Ed will head over to your channel and do the same.
@@montana2strokeracer Thank you Dale.👍
I really appreciate that.
Looks great.
Thanks John, it is a fun project, really getting in the weeds on this one.
You do a lot of machinist work for not being one , and having a milling machine in your shop kinda qualifies you as one
Thank you, I am still learning every day. I like to mix the machine work in with the bike maintenance to show what most never see.
Dint sell yourself short brother,your a good machinest...
Thanks Ken, I do try. Thanks for watching
Very interesting thank you for the info.
Thank you and thanks for spending time with me in the shop.
Wondering if the low spots would be a good place for the notorious JB-weld?
Hey Mark, man that JB weld gets a bad rap sometimes, it is very useful in many ways. I actually thought it would be just as good a welding this at the base anyway. Just sided on the more permanent repair instead.
hey, where is everybody? Oh well am here to help!
Frank is helpful! Roger that. Thanks Frank.
Good job brother.
Thanks Cain, I sure appreciate you spending time with me in the shop!
Yeah, it always takes more weld than you think. It'll be fine.
I mill a lot of aluminum, and use a much higher speed.
Are you really sure that's an RM cylinder and not a PE? I can measure the exhaust port height on mine for you if you want to find out for sure...
Nice video, as always,
Robert
Hey Robert, yes absolutely sure it is RM, the PE exhaust ports are about .095 lower. This is a 1978.5 cylinder; you probably saw the rubber insulators. On the PE they go in the vertical gaps on the fins, these go horizontally between fins. Not all RMs got insulators, only a few in 78.5 model change. The 76 cylinder is a completely different bore at 70mm, and it has the vertical slots between the fins, the 77 through 78.5 have 67mm bore 70mm stroke, the 77 and 78 has no vertical slots, the 78.5 has the return of the vertical slots and some got the round rubber insulators between the fins. Also, some porting up grades.
Glad to be one of the 30%
Thank you very much, glad to have you on board and hope you enjoy the videos.
any advantage to porting and polishing a 2 stroke?
Oh sure, lots to be gained, but for a 70 year old trail rider. Not worth the effort.
Yes you are pro Peace out
Did you consider using a pipe centre to support the workpiece?
Hi there, you know I really didn't consider using a bull nose center. I guess I did not think there was enough stick out to warrant it. Some others have said that it can put too much pressure on the bottom of the sleeve and break an ear off. I don't know that firsthand though. I think if you were cutting further out you may need to stabilize it somehow, may be with an expanding mandrel or something to that effect.
Hlo sir, which engine is more durable suzuki or yamaha??
Hi there, in the 70's-time frame I would have to say the Suzuki's were more durable. There were a lot more Yamaha's made though. So, lot more parts, new and used out there. Just my opinion of course.
Why wouldn’t you reface the whole cylinder base square to the bore .
Hi Jim, that would be nice but not necessary and it causes other problems. I briefly covered that in the video. But it would have probably taken .020 to clean it up, then that brings your ports down .020, so you would have to go back in and raise all the ports the .020. Then since the rod is going up toward the head .020 more, you would need to recut the head to remove .020 so the compression wouldn't be too high, and the squish area in the head would need recutting also to prevent pre ignition. So, you can see by changing one thing it is just a snowball effect that just has too many other consequences. Good question though. Thanks for spending time with me in the shop.
Beatifull job mate !
Thank You Jorge!