MTFCA Forum

Looking for feed back on these new drums from people who have ACTUALLY run them a while.

Just finished a motor re-rebuild for a customer. motor had around 2000 miles since 1st rebuild. There were other unrelated issues. tranny drums had quite a bit of wear. (not rivets). Running wood bands. I assumed the last guy didnt address them during the rebuild. to my suprise, all 3 were new ductile drums. my first experience with non original drums. I have run original restored drums well over 10k miles with kevlar that show no wear. Between drums, metal deposited/transfered from drum faces to gear flanges.
Turned drums, none ran perfectly square, have seen way worse. took .005 -.008 to clean and square. they were nasty to cut. i normally use a sharp carbide cutter. they didnt like that. tried hi speed cobalt cutter - better. cut like T-0 aluminum as opposed to T-6. very soft. ended up grinding & smoothing.
balance was close, as expected with a C&C part.
I contacted a mfg of this type of drum. he could not confirm a hardness, & never got back to me on the subject.
could be soft drums, metal shavings between band & drum, wood band material, a combination. ????
any similar experiences?

Looking for feed back on these new drums from people who have ACTUALLY run them a while.

We need to know which new drums are you asking about?

dont know exactly. there is no name on them. i believe they are new ductile iron. i dont want to take a guess & wrongly call out anybody.
that dosent change the question.

Looking for feed back on these new drums from people who have ACTUALLY run them a while.

If you have run any of the new drums a bunch of miles & looked at them, contribute. if you know who made them , identify the manufacturer. maybe your supplier makes a better drum. thanks - john

John

Installed new J&M ductile cast iron drums in my '27, and used new wood linings as choice since the drums were new.

Some wear noticed using wood linings. Had about 6K on these when I pulled the wood linings. The worn low band wood lining was the reason to pull the bands.

Changed to Kevlar, and on inspections after another 3K, drum surfaces haven't changed from this photo of the wood linings being removed. Think the wood is harder on the metal, as only small oil grooves to feed oil. The woven Kevlar drinks oil.

Note lines worn in low drum surface, not real deep, but could feel with fingernail passing over.

thanks dan. thats what i found. could be the wood bands. One of the issues was hard pedal pressure & grabby when hot. I replaced the wood with old scandia. not a fan of wood. i can see advantages in the montanna 500, but not a touring T. (just a personal opinion, hold your fire).
I am hesitant to use kevlar on customer motors. seen to many cracked drums from operator error & folks overadjusting &thinking you adjust for pedal travel, Even after stern warnings. one guy did it twice. I, myself run kevlar in all my T's.
I believe religiously that kevlar must be adjusted with the engine running. I run outside band adjusters on all pedals personally. tighten untill you hear the tripple gears just starting to growel (the slightest change in sound). then back off 1/2 turn. thats perfect. more drags, less is wasted pedal travel.
of course this method works for any band material.

i may have just awakened the beast.

Not to nitpick something but to educate "as expected with a C&C part." the term is CNC and stands for computer numerical control.
I just retired form 35 years of repairing them.