TURBOVMAX
Well-Known Member
Do you have any pics of the failed gear? What do the drive dogs look like after the failure? Also a little bit more info on your setup would be helpful. Cush drive on the rear wheel?
Drag Race Transmission/Clutch
- Thread starter TURBOVMAX
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Do you have any pics of the failed gear? What do the drive dogs look like after the failure? Also a little bit more info on your setup would be helpful. Cush drive on the rear wheel?
TURBOVMAX
Well-Known Member
Sean,
I would say there a lot of factors that could contribute to tooth failure. One is the dogs getting rounded. The early Vmax had that second gear problem under normal loads. The bike would just keep trying to engage second gear (surging) as you know I'm sure. That happens a lot quicker at the drag strip and the shock load to the gear tooth goes through the roof.
I'd like to see some pics of that gear. Do you have any pics of broken gears?
On the hardness... very rarely do engineers harden anything beyond a 62 rockwell. That's glass hard and normally parts that are that hard, are only case hardened to about .060 max depth.
Gears are not normally hardened beyond about 50 rockwell. The reason... is that they would rather see the tooth flex and not break because of the hardness. Hardening does not make anything any stronger. It's used for wear.
The core material along with the cross section at the root of the tooth in gears is actually where the strength is. The problem is simply the horsepower your trying to put thorough the tooth profile. That's why those gears for the funnybike tranny are so big and wide. That and they use a better material for the gear.
Gotta go to work now, more later I'm sure.
I popped the number out from memory but want to say it was right. That was from a guy that build 600+ rwhp turbo bikes that were used strictly for street racing (money races). Of course they weren't Yamaha's either which was a bummer. On most streets he kept the boost down around 20psi (250-300hp) because it would only spin the tire worse with anything higher then that.
The early transmissions used the side of the gear teeth to engage the second gear and not the typical 3 dog setup like now. So it was trying to engage a crapload more surface but of course harder to mesh up.
I would agree for sure about surging and "shocking" the teeth is definitely asking for failure but I am very surprised the dogs aren't gone. I shredded one trans (multiple gear failer) and later found out the driveshaft I was using was 1/8" too long (sportmax shaft) which I think was preloading the cases and causing flex. I wonder if that isn't part of what is going on in his trans problem.
As you noted, the big wide teeth would hold a crap load more power.
Another thought would be a cryo process or maybe even a nitride process. make it have a harder shell but still softer inside for flex/deflection.
Sean
The early transmissions used the side of the gear teeth to engage the second gear and not the typical 3 dog setup like now. So it was trying to engage a crapload more surface but of course harder to mesh up.
I would agree for sure about surging and "shocking" the teeth is definitely asking for failure but I am very surprised the dogs aren't gone. I shredded one trans (multiple gear failer) and later found out the driveshaft I was using was 1/8" too long (sportmax shaft) which I think was preloading the cases and causing flex. I wonder if that isn't part of what is going on in his trans problem.
As you noted, the big wide teeth would hold a crap load more power.
Another thought would be a cryo process or maybe even a nitride process. make it have a harder shell but still softer inside for flex/deflection.
Sean
chainednitromaxx
Well-Known Member
Yes ,the gears are shearing teeth off the gear face,the dogs are fine.I did try cryogenics but no good.Never tried heat treating.I talked with Gainey at PCW and he mentioned that if the gears are made to be harder but yet not enough gear it may be prone to shear just as easy since the gear will not flex just snap.Sorry can not remimber as in depth as he went and that was not word for word. Do you think heat treating would help?I have always wondered if someone would vest in redoing 1st and 2nd for the max it would get alot of demand. I do know the old 2nd i think in 85 86 had wider gear area,what i am trying now but you can not find those old gears anymore hardly. Funny thing is i believe those where the ones everyone was throwing away!
chainednitromaxx
Well-Known Member
Ok, i did find one of the gears in my garage with one tooth sheared off . I will try to get a pic of it on here if i can figure out how.There is some wear on the dogs but not alot to me. My bike is 70" wheel base chain drive set up pcw.The bike has a Kosman with spools no cush drive like sport bikes.Front end has mild rake with full chromoly head with head bearing droped 2 ".I do know this, the frame is tweaking badly and i am adding support to help it.
Yall are right i am shocking the gears alot.I set the nos controller to launch at 50% and time to full in 1 second.It is full throttle bottle spraying on green light,the only thing that kills the bottle is the wide open throttle switch.It does NOT have any ignition kill for shifting gears or air shifter.I have been afraid of killing ignition since sprying nos.I shift by snapping out of throttle and grabbing next gear with no clutch.It is usually at about 7 or 8 o clock in first and second in the shift. lowering to ground at end of second. High 1.30s 60 ft.Really appreciate the tech and help on this subject alot!!!!!! Oh yea it is full suspension in back and i do run this set up with dot sc2 street tire pirille diablo race take offs i buy used off e bay 17 rims.Maybe this info will help.
KJShover
Proud Vmax lover
What I did with the drag bike was wired the ignition kill with the solonoid after the progressive. No issues with spraying while the ignition being interupted. I've know a few others that didn't bother and had no problems.
But, I didn't have thier $$ and wanted to be a little safer.
But, I didn't have thier $$ and wanted to be a little safer.
I think I have a box load of the early trans gears if you want some.
Sean
Sean
TURBOVMAX
Well-Known Member
High 1.30's on a Pirelli take off with no bar... I'm impressed! What kind of numbers do you run? Heat treating the gears will not make them any stronger. If you have a problem posting the pics you can just send them to me and I'll put them up for you. [email protected] Usually a missed engagement of the gear is accompanied by a bent shift fork. It dosen't take much rounding of the dogs to cause that kind of a problem. Not saying that it's your problem with breaking teeth.
I would spend the money and get yourself an airshifter and don't worry about spraying with it. The second thing that will help, is to get yourself a Sertco Torsion Sprocket. The bad news is they don't make them anymore. But you can find them on ebay or dragbike.com classified's once in a while. If your using a Kosman it should bolt right up without doing any machining or respacing of the rear wheel. If you can't find a sprocket find a wheel you can mount up with a cush drive. How many teeth are you running on your rear sprocket?
The stock gears are designed to stay engaged... some times the people doing the back cut on the dogs do more harm than good. My experience with those who don't know, is that the cutter leaves a sharp line at the base of the cut which is call a stress raiser. That is where the dogs will break off if the back cut is not done properly leaving a nice radius there.
The thing that will help most is to have your stock gears shot peened
Why no cut on the first two gear dogs?
Take a look at the tire on my bike coming out of the hole. There's no way that your Pirelli is hooking up that hard. Since I've stopped undercutting those 2 gears I have no problems with broken dogs or broken gears. If it ain't broke don't fix it. Once the bike settles out, there's no problem with cutting those gears. I just do it to those gears, because it will help with keeping the gears engaged.The shifts are a lot easier for the transmission to make (less load on the gears on shift)
chainednitromaxx
Well-Known Member
Yes i would love to be able to get some of those gears.I can give you a call if you like to set this up. John
chainednitromaxx
Well-Known Member
TurboVmax
The bike goes 5.90 to 6.00 using the whole lane(does not go straight from frame flex)at 119mph to 120mph with alot of clutch slipping(they are black when i change them).I have not went to lock up yet since the tranny busting but looks like now yall gave me a game plan and see the lock clutch coming.I have to run the right lane and actually point it slightly towards the guard rail only to end up far far left at my 1st to second shift.
I will search for the sprocket and i also had been thinking about r1 rims since i weighed some and they are lighter then what i got,My rim goes 37lb with tire!!!!!!!!!The sprocket is a 40 tooth.
I will leave 1st and 2nd alone on next set except and try this.The pic you posted really has the bike digging.I am sure that tire hooks better but you really should try a sc2 180 or 190 at 10 to 11 lbs one day,they are like glue for a street strip bike.
One2dmax and Turbovmax i thank yall for the info,It will be awsome if this works better because i really miss the track and upsetting people on my max.
The bike goes 5.90 to 6.00 using the whole lane(does not go straight from frame flex)at 119mph to 120mph with alot of clutch slipping(they are black when i change them).I have not went to lock up yet since the tranny busting but looks like now yall gave me a game plan and see the lock clutch coming.I have to run the right lane and actually point it slightly towards the guard rail only to end up far far left at my 1st to second shift.
I will search for the sprocket and i also had been thinking about r1 rims since i weighed some and they are lighter then what i got,My rim goes 37lb with tire!!!!!!!!!The sprocket is a 40 tooth.
I will leave 1st and 2nd alone on next set except and try this.The pic you posted really has the bike digging.I am sure that tire hooks better but you really should try a sc2 180 or 190 at 10 to 11 lbs one day,they are like glue for a street strip bike.
One2dmax and Turbovmax i thank yall for the info,It will be awsome if this works better because i really miss the track and upsetting people on my max.
Shoot me an email and i'll dig through the pile. For now it will only cost you shipping!
Sean
Sean
hubeerjw
Well-Known Member
Watch out ChainDrive..... Sean is suckerin ya in....
I finally figured out how Sean does it.... he plays the nice guy saying, "Oh, sure, I can send you those parts.... just pay shipping" You think to yourself... "dang... what a nice guy!" Next thing you know, you ordered 3 motors, a couple of flankter gurders, your wife is pregnant, and you can't seem to remember why you even talked to Sean in the first place...
Warning to all... Morley is way too nice!!!!!
unk:Once again Sean, going over and beyond what is needed.... :cheers:
I don't think she ended up pregnant until AFTER I spent the night??
Sean
Sean
hubeerjw
Well-Known Member
You, Sean, and Gary and way ahead of me for experience, but Sean made a comment about the longer driveshaft that got me thinking. Would it, or could part of your problem be associated to your frame and swingarm flexing? Either causing the chain to bind or not having the right chain tension set and causing some sort of pulling or surging on the transmission? It would be neat to see some vids of your runs. There is also some free software that will dissect the video into individual frames and that can tell you quite a bit. I watched a launch where I wheelied pretty hard and it was amazing to see how the bike and I reacted. I have no clue if I am on track or not, but thought I would throw it out there. I have solid motor mounts on my drag bike and it seems to be running pretty straight, but I'm not able to push my bike like you are.
Jeff
Jeff
TURBOVMAX
Well-Known Member
One of things about racing a Vmax that has always annoyed me is just being able to get parts so that you can. If you can find them, their always more expensive than if you were to buy for an inline bike.
I'll post up some info tomorrow on how to buy or make an inexpensive lockup clutch hat for your bike. Maybe we can get someone on the list to make a cover extension and spacers inexpensively.
I'll post up some info tomorrow on how to buy or make an inexpensive lockup clutch hat for your bike. Maybe we can get someone on the list to make a cover extension and spacers inexpensively.
chainednitromaxx
Well-Known Member
Outstanding! i will get in contact with ya on the shipping.Hang on to those old gears i am sure i can use them.
chainednitromaxx
Well-Known Member
HUBEERJW
oh yes i am sure the frame flexing does not help.There is some custom chromoly pieces being made for it now to help.Its hard to keep the frame tight with me keeping full suspension and oversized gas tank under seat.Motor is out being freshened up so now is great time to do it with motor out of the way.The bike stopped going straight when i managed to go from 6.35s to the 6.00s. It is like night and day those 3 tenths.I would have never thought it was i big difference till i had to get the balls to launch it harder(scary)
oh yes i am sure the frame flexing does not help.There is some custom chromoly pieces being made for it now to help.Its hard to keep the frame tight with me keeping full suspension and oversized gas tank under seat.Motor is out being freshened up so now is great time to do it with motor out of the way.The bike stopped going straight when i managed to go from 6.35s to the 6.00s. It is like night and day those 3 tenths.I would have never thought it was i big difference till i had to get the balls to launch it harder(scary)
blvdblaster1200
Well-Known Member
JOHN ,when you get your bike back together id like to ride up and watch you race.ill pm you around the season start. later mike
