Ok heres the deal..... First this is an '08 M8, so mechanical reverse. Two weekends ago I used reverse and after going back into forward I don't know if I just didn't wait long enough or what but when I hit the gas I got a terrible grind. Nothing I could do but wait for the clutch to disengage in horror. I fully expected to be completely screwed (I was NOT in a good place to get "towed" out). I caught my breathe and tried to go and everything was fine. Rode the rest of the day and then the following 2 days (never used reverse again). Going up this weekend but not figuring there will be much, if any, riding due to the weather. Hoping for at least one more trip in March conditions permitting. Figure if it lasts i'll wait until summer. Now after my story, the question..... Anything particular that should be done? Obviously I will pull the DD and change the oil and try and take a look for any damage or metal in the oil but are there any parts of pieces I should just plan to replace or take extra special notice on?
Diamond Drive Experts - Grinding Question
- Thread starter scottd
- Start date
we had the same thing happen to our 07 F5 on out trip up north this year. Dad was riding and i figured that he didnt let the rpms get all the way down to idle speed. sounded horrible, but sled ran just fine after that and we have now put another 200 miles on it since then with no issues.
Did the same thing with my '10 F6 this last weekend, switched from reverse to forward before it got to idle. Heard the same grinding noise. I shut down the sled, waited for a couple seconds, and started it right back up. Both forward and reverse work fine.
I would say just wait until you hear the idle before you switch from reverse to forward in the future.
I would say just wait until you hear the idle before you switch from reverse to forward in the future.
camphappyplace
Member
I had the same thing happen to me riding my 2009 M8 with electronic reverse two weekends ago. My son and I were riding off trail in the UP in an area that would not have been easy to drag it out. I was turning around in a confined area. It was an ugly noise. My son was sitting on his sled waiting for me to turn around and he could hear it above his idling motor. Made us both very nervous. Once I was turned around I turned it off and then restarted. No more noise the rest of the day. It ran great. I know there's numerous threads on various websites about a "bad" bearing on certain Diamond Drives. I think I'll replace the bearing they talk about this off season. I have only around 500 miles on the sled but I feel I'm tempting fate by running with the stock bearing.
favoritos
Well-known member
Scottd, I would look at the motion on the shifting fork and the solenoid. Some of the solenoids did get sticky and or failed. It is possible to have a bent shifting fork, but if it is running good now, I would rule that out as a problem.
Camphappyplace, is it possible that the belt was slipping? Sometimes the roller does not catch the notch and the sheaves will open causing quite the ruckus. I would change the DD fluid if you are concerned about the bearing. Just look for any flakes in the fluid. It seems unlikely that you would have finished the trip with the DD gears slipping/grinding. Once they start to go, you better be headed toward the trailer.
Camphappyplace, is it possible that the belt was slipping? Sometimes the roller does not catch the notch and the sheaves will open causing quite the ruckus. I would change the DD fluid if you are concerned about the bearing. Just look for any flakes in the fluid. It seems unlikely that you would have finished the trip with the DD gears slipping/grinding. Once they start to go, you better be headed toward the trailer.
indy_500
Well-known member
I know this is off-topic but what are some advantages of DD?
All i see is it's more expensive, hard to regear, seems to be unreliable, hard to work on, and if it was that great wouldn't other brands have come up with something? Did they go to this so they could free up some space on the exhaust side?
All i see is it's more expensive, hard to regear, seems to be unreliable, hard to work on, and if it was that great wouldn't other brands have come up with something? Did they go to this so they could free up some space on the exhaust side?
cuzzinolaf
Well-known member
I blew my diamond drive on my old 2008 M8 in Rabbit Ears, Colorado a few years ago. We were a mile from the trail and in some deep snow and the track was completly locked up. After putzing with it for a while I tried to put it into reverse and then shut it down... freeing up the track to be towed out. Keep this in mind if your DD goes out in the woods or wherever.
favoritos
Well-known member
Main thing is to move all the mass of the drivetrain down into the tunnel. The brakes still work if there is a failure anywhere as well. Not sure why they made the things so complicated inside the case? They could just run the engine backwards and make it a simple gear to gear case instead of the complicated planetary system. Just kidding. I do understand wanting less rolling mass in the drivetrain, but the elimination of the second shaft creates a more complicated gearcase. Reliability is about par with standard chaincase sleds. Remember to compare reverse chain drives to reverse DD drives.
We are running more power than ever through the drivetrain now, so the systems are stressed further The CF and M sleds make the issue worse because the motor mounts are squishing and allowing the belt to slip. This causes chatter in the drivetrain and ultimately stresses the bearings even more on the big hp sleds.
camphappyplace
Member
Favoritos - based on what you're saying, it very well could have been the belt slipping. Like I said, it ran like a top the rest of the day. Thanks for the input.
I think I either hadn't waited long enough after hitting the button and/or in the 'situation' I was in possibly there was still enough of a load still on it (just guessing no idea) that it didn't go at first??? Once it was in everything was fine for the rest of the weekend and a lot of riding. I never did use the reverse again because first I was/am a little scared to mess with it and second never needed it. I am much more concerned about any internal damage to the planetary and gears. I guess I will see what I see when it comes apart this summer (I hope it lasts until then) and make a decision based on what is in the oil and what things look like.
There are probably patent issues also. If the bugs can be worked out of it, you may see other manufacturers use something similar also. They all said Cat's front-end suspension was inferior and now they have all adopted it.
booondocker
New member
It's always about patents and payments...which none of the makers want to pay to use.
Let's see....all gear system compared to gears and chain drive with tensioners and reversing processes.
I will take the gear system any day of the week...as long as you aren't trying to mess with gearing the sled down.
Chain drive is old school....same as trailing arm suspensions. When it comes to "moving over" it is ALWAYS about what it costs to do it.
If DD was not ready for prime time, Cat would not be using it more and more.
Let's see....all gear system compared to gears and chain drive with tensioners and reversing processes.
I will take the gear system any day of the week...as long as you aren't trying to mess with gearing the sled down.
Chain drive is old school....same as trailing arm suspensions. When it comes to "moving over" it is ALWAYS about what it costs to do it.
If DD was not ready for prime time, Cat would not be using it more and more.
the 07 08 is a time bomb .I would at minn pull it apart and if you are around 1000 mi or more with out question replace the 5pinion gear with a BDX 5pinion gear. that is the week link and should be considered wear items when it goes it can and more times than not take the rest of the drive with it $160 bucks worth every dime .my 08 went I replaced with BDX lite drive and rewired harness to get 09 motor reverse.you can feel the diff in motor spool up with out all the 9lbs of reverse crap spinning around in that case.also some guys are pitching the servo and more or less adding a Handel to the lever that goes in to drive so you reach down turn it and know it has locked in and out.