Was going through some of my paperwork and came upon this stuff. Thought some of you may be interested.

Before I got my guy started on assembly of the new build I sent my gears off for undercutting.

How many have done this?

I also upgraded all of my shift forks to the newer (harder design) and bought a new shift shaft.

In case any of you want info on who can do this work and cost. . . here you go:

Mark Doucette (Owner of R&D Motorsports) was great. You can reach him at 260-728-9457. R+D Motorsports, 1632 N. Hercules Ave., Bldg G, Clearwater, Florida 33765.

They first magnaflux the gears (check for cracks - no need in working on a tranny that is cracked) This cost about $49
They then undercut the engagement dogs so the more pressure that is applied (in the form of Torque) the more the gears want to lock into eachother. The cost for this is about $225. Turnaround is about 5 business days.
Total for these services is about $329+$15 frt. (can't remember where the extra costs came from.)

They will also send off the gears for Kryo treatment which pulls the harder martinite (black) to the outside of the molecules where some stock transmissions have metal that the softer austinite (white) part of the moleucle is on the edges. (I guess I should have said. . . "for the engineers in the group" first!)

I didn't do the Kryo treatment. I think it was about another $150 for that.

When he did the Magnaflux he said he noticed a little cancer on the first gear. Said that usually happened when the bike has been sitting and the clutch plates are stuck together. . . once it is started and you put it in gear you get a clunk or maybe just a little snap. . . said that can cause the issue. Nothing to worry about since the wear was so minor. My YFZ426 does it all the time too. Stiffer springs probably don't help (they probably squish the oil out [img]i/expressions/face-icon-small-confused.gif[/img] )

If you are experiencing missed shifts from first to second and it is getting worse and worse, I suggest replacing your shifting forks and at least looking at your engagement dogs. A friend replaced the forks but, didn't do the undercutting then had to get into his cases a second time because he had worn his engagement dogs to where they wouldn't stay together. There should be some other threads on this issue.

 

Mark,

I take it you just sent the lower unit, as-in NOT the jug etc, just the tranny? Who did you use for your carrier? And, did you purchase shift forks and shaft and send them or did he take care of that part? TIA...

 

Jim:

Just sent the gears. The cases were split on this engine when I bought it so, that was one of the first things I did. You'll have to get them out yourself then send them off.

The shift forks have been updated from Bomb./Rotax (all the new engines have the new - harder ones.) I just bought the new ones from the dealer - I know some people have had those kryo treated as well.

Is your tranny popping out of second gear?

 

Poping out really isn't an issue....but I've missed shiffted many times in the past. I'm getting better tho--starting out in 2nd![img]i/expressions/face-icon-small-wink.gif[/img] I've got what my doc calls a "drop foot" acquired after hip surgery nerve damage--have to turn my foot up sideways or lift my leg to shift...I look spazmatic for reasons other than just genetics![img]i/expressions/face-icon-small-blush.gif[/img]

Afterthought...were you able to do the reassembly yourself or did you have someone else take care of that part? $$$?

 

Mark, It looks like your creation of the monster motor is comming along with the ut-most attention..congrats!

It looks like I will have some tough competition at Dumont when you come out..

 

I am having someone else take care of the re-assembly. This engine was torn completely down and numerous parts were replaced. The guy we use is very reasonable for this kind of work and he is pretty quick about it too. He has put together quite a few big bore bikes in the last few years.

Mario:

I am building it right. Won't have a swing-arm for a while though. Can't wait to feel the POWER. I think you will be able to take me between your tuning, swing-arm and alky. I'll have fun anyways!

 

Thanks for the confidence, but ill only have a 720 and it will be on gas for a few months [ of course nitro prop if neede LoL], so I think when you come down to Dumont this season we'll dial the bikes in against eachother on the hill and find the perfect jetting for you, then we will know where you need to be for Sand Mountain. Youll apreciate the dialed in big bore torque.

 

I also had my tranny "back cut" this past winter. I sent it in the MRE in Florida. I did all the dis-assembley,and re-assembley myself. It wasnt that bad at all, but I had people like DSmike, Scooby,and Jeffinrivercity to call when I had a question.[img]i/expressions/face-icon-small-smile.gif[/img]




Biggerisbetter.