DD Clutch Mod

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desert_max

desert_max

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Guys,

Please don't hate me. I'm pretty good at searching things out and that's why I don't post so much - I usually just lurk.

But, my clutch is going out and I've accumulated parts to replace it. But, I've seen a few references here on the DD mod which is something I'd like to include in the job.

Danged if I can find a post or thread that describes the modification - and I have spent some time looking. Does anyone have a bookmark to a thread on this mod?

Sorry. (and thanks in advance).

As I understand it, it seems to involve adding an extra plate and/or friction disk...right?
 
You guys beat me. Just came back to post the link and there were responses. this forum rocks:punk::punk:
 
I have a double depth spring retainer for the Gen 1 to accommodate both springs when stacked. If interested.

rick rash
 
The DD is a good mod and will prevent clutch slip, this is hard on the drivetrain if you hammer it through the gears, another option would be to install a PCW spring, a little heavier than stock and works well, I know a lot of Maxers here run the DD mod with good results but I have heard of issues too, just wanted to throw that out there.................Tom.
 
Thanks yet again, guys.

I've got the spring from the "parted '85" to use in the mod. I don't know how "used" it is, but hopefully I won't have to grunt too hard in traffic. I'm not too worried about drivetrain abuse. All VMax's are run hard, but not all are run hard all the time.

I'm somewhere in the middle, and will take my chances.

Also, If I find I need the "alternate" retainer, I'll let you know, RR. Thanks for the heads up on that retainer.
 
I had a spare diaphragm spring on-hand when I renewed my clutch, but I went w/the PCW extra-friction plate and OEM friction plates kit. It comes w/the engine side cover gasket. I upgraded to their heavy-duty diaphragm spring, too.

I didn't want the DD heavier-pull in stop & go traffic. With the PCW spring I cannot honestly tell the difference between the stock pull and the PCW heavy-duty spring pull.

Running into the higher rpm's and then shifting gives a very satisfying surge as the clutch engages. I don't speed-shift even though I have an undercut tranny.

If you try the DD and decide the effort is too-much, it's easy to remove the extra one. In any case, the extra friction disc is worth the trouble, whichever way you go.
 
Don't do it I snapped a shaft and had to repair 3rd gear after the DD mod plus unless you do a different clutch master you will hate it. I can not prove the third gear issue is related to it but I have my suspicions. I ordered the under cut gears and PCW heavy duty clutch spring and repaired it. The PCW spring is the way to go. good luck.
 
I dont agree that dd hurts the bike. Beekeeper broke his driveshaft and he runs a pcw spring. If you beat on any bike it will need repair. I feel its more to do with how high you run your rpm up in between the gear when you shift. I think its got a lot to do with the back lash play on the drive shaft. Over time of beating on it I think the driveshaft get strees fractures and ends up braking sooner or later. If you blow third gear I would have to say that is on the rider.my bike had a dd in it for 15000 miles and dident brake a driveshsft until 14000 miles and for 14000 miles I had a lot of hooligan fun. My drivesfat broke at thunder and I did hit it that hard. When I got on it in the parking lot it snaped like a tooth pik so that tells me the driveshaft already had damage before I did the holeshot. I went to the dragstrip and did 30 passes and never broke a shaft. But I bet I did damage to it. Todd snaped a few shafts at the track and I now he shifts harder than me 1st to 2nd. And that will do more damage to the driveshaft and sooner or later it will brake. Will the dd do more stress to the driveshaft than stock clutch yes it will. And the same goes for pcw. My point is the dd set up is not a voo doo curse. Its just a bad ass clutch set up that works great for drag racing. It also helps the clutch last a lot longer. If you dont do much hooligan riding than the stock set up is good for you. If you do alot of hooligan riding and no drag racing than pcw is good for you. if you do hooligan riding and drag racing than the dd set up is good for you. If you do hooligan riding with a stock clutch you will smoke a clutch and have to replace it. if you run a shinko tire and do hooligan riding it will take a stock clutch in a short time. Also just to let you know its not hard to change a driveshaft.
 
Uh oh. I'm a frequent hooligan with a Shinko who tries to get to the track a couple of times a season. Three strikes.

DD it will be...maybe this weekend if I get time.
 
^ Mike's assessment is pretty accurate.
As long as you ride knowing that your clutch is no longer the weak point in the drivetrain you shouldn't have an issue.
Just be careful on your 1st-2nd shifts if you do the DD Mod.
The stress that was absorbed/displaced by the Slipper part of the Clutch (1/2 friction plate, etc.) and weaker single spring is now being transferred to the transmission and drive shaft.
Most of the maxes I've seen and read about that blew 2nd gear had the DD Mod and the riders tended to power shift (No clutch used) so I'm sure there is a direct correlation there.
A few guys have some good info on riding a Max with the DD Mod here:
http://www.vmaxforum.net/showthread.php?t=25171
Also if you run a Shinko TM-230 Rear be careful when doing Burnouts because you are Much more likely to snap a driveshaft due to the better grabbing clutch and the stickiness of the Shinko tire.

Personally I went with the Barnett Spring conversion and like it a lot.
I don't run my bike on the Strip but I do tend to launch pretty hard from just about every stoplight/stop sign (front wheel skipping in the air from 1st through 3rd).
It grabs better than the stock clutch but nowhere near as stiff as the DD.
The shifting seems smoother and the clutch his still the weak link in the drivetrain.
 
Last edited:
Don't do it worst mod I ever did to my bike cost me over 800$ and a summer off from riding due to breaking the trans and driveshaft almost a week from each other. Go with just a brand new spring works just as good and a lot easier on parts. clutch is cheaper than pulling your motor and fixing a trans .
 
DD for 15k miles, no issues. I like the quick disengage the DD gives. For good positive lock up, it's an economical way to go. To get as much power to the pavement as possible, you have to do something with a stock Vmax clutch setup. A used 2nd spring is best IMO.
 
I broke a driveshaft first time I rode it with DD, blew out second gear later on.
Both happened on hard 1-2 shifts.

After all the strip time I'm sure 2nd's number was up anyway.

HARD 1-2 shifts with the DD seem to be an underlying contributor not that these things do not happen with out the DD being installed.

I went to a PCW spring on my new
Motor.
 
If you blow 3rd gear it is on the rider ? Then why do they make a fix for the transmissions if it is a rider problem? I didn't blow 3rd it kept popping out but still required a undercut gear set to fix. I hated the clutch feel of the DD. I also drag race and ride like a hooligan with a Shinko. It looks like I am not the only on with this opinion. I have to agree with worst Mod ever.
 
These things shift like a goddamn tractor from the 40's anyway, do the DD mod but install an air shifter... I've broken one driveshaft but been running strong beating the hell out of it running mid 10's with a big guy on it and the trans still shifts like it did when I got the bike.

Sent from my ADR6425LVW using Tapatalk
 
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