Hey everyone. I wanted to post my feedback using @kevjayney
photos that he posted and the procedures he outlined. I was forced into replacing the sprag myself because i noticed my bike began experiencing the exact same issues described by others despite having a lithium battery kept charged at all times, along with better ignition cables. As well the only dealer in my area stopped handling MV, so it was just easier for me to do it myself. That's ok, I like (sometimes) getting into the guts of a machine.
At first I thought I might be able to tackle this replacement without removing the airbox and throttle body as he describes in his procedures, but unfortunately that was not the case because in order to remove a couple of the bolts holding the sprag housing in place in the rear, the only way to get in there is as he describes.
First off let me say that kev's photos that he posted earlier are spot on every step of the way. I found I was able to move the throttle body aside without disconnecting everything, but that's probably the only exception I've noticed to his photos.
Before you begin, I highly recommend the following:
- flex adapter for your hex/torx bit drivers
- solid 5mm and T30 bit. Yes, I know this is obvious, but a few bolts are really tight. I came close to stripping a couple myself.
- some type of elongated handle, wrench, extension...whatever.
The last part I suggest this for added torque in removing things. When working on my bikes, I typically use 1/4" drive tools, so a 1/4" ratchet sometimes isn't large enough for a couple of items to really lay into it if you have to.
Airbox - the first problem with tight, small bolts
The first place I came across a problem was trying to remove the lower part of the airbox in order to expose to top of the engine, ignition coils, etc. There are 2 5mm hex bolts that are very tight and you don't have much room for a standard hex bit to fit in there. A flex adapter for your bit can help here. I already happened to have a flexible 5mm hex bit, but most people may not have this and instead a flex adapter might be more of a universal solution. I like Snap-On myself, and item TMU8B would work. The 5mm flex bit I used was TUAM5E.
Starter - two problems for one component
The second area that was a problem was the removal of the starter itself. There 2 bolts holding it in place just as kev describes in his photo, but the problem is that there is no way I found to remove those bolts with a straight bit. I also tried using my T30 flex bit...no luck. The reason why is when I use a flex adapter, the more it is flexed (meaning not straight), I usually dont apply as much torque to loosen because I always worry about the bit slipping and then beginning to strip the head of the bolt. What's interesting about these 2 bolts is that even without any major disassembly of the bike, you can see them on the outside plain as day. The main problem is their location almost immediately below the frame itself. Even with a stubby torx bit the total length of the bit plus a ratchet is too much to fit in there. I don't know how kev did his, but I've attached a picture of what I used to get to mine.
In the first picture I have a standalone T30 bit and a flare nut wrench. In the second picture is my simple assembled solution. Now I suppose you could use a standard open end wrench, but I don't like using those types of wrenches at all because when you put torque on them, there are only 2 contact points and they are typically near the corners and they have a tendency to start to round them off. A flare nut wrench will not do this. You could also use a 6 point box wrench which would probably be better, I just didn't have one available in that size.
Moving on, the next problem I had was removing the starter itself once the bolts were out. I simply could not do this. I could not get enough room made by moving the cables and such around, combined with the starter location and pulling it out toward the frame. So I had to leave the starter in the general area while I then proceeded to work on removing the 5 bolts for the starter housing. (third picture)
Sprag housing and an important warning
The last part of my post is, in my opinion, the most important
, so pay attention. Don't make the same mistake I did. When removing the 5 T30 bolts of the starter housing, it is very important to keep your wrench as perfectly straight as possible so that the bit does not slip. I had difficulty with the back 2 and these 2 bolts were very close to becoming stripped out. Why you ask? Well this is the first time I've removed this housing on my bike and you notice the black gasket forming material they used at the factory solidified a bit and can see it from outside the housing. Well, when they applied that gasket material they were generous with it and indiscriminate in how they applied it. All of the bolts I removed had the gasket material on them. This was one major reason why I had to put a bit more muscle than I normally would. Again, I used good bits (I mentioned Snap-on didn't I [IMG class=inlineimg]http://www.mvagusta.net/forum/images/MVagusta_net_2016/smilies/tango_face_smile.png[/IMG] ). My standard T30 bit plus my small 1/4" wrench were able to fit but the ratchet itself was too small to get the needed torque onto the back 2 bolts. I lucked out and had a longer wrench with 1/4" head that I nearly forgot about and was finally able to rescue those 2 bolts.
I managed to get maybe 5 good tries on those back bolts before they were dangerously close to becoming stripped. Thankfully I was able to get them out with the longer wrench that was able to hold very steady and give me the necessary torque to get them loose. I am going to have to order replacements though as there is no way those are going back on my bike.
The gasket material being on the bolts isn't really the main reason why those back 2 were difficult to remove, but it isn't helping the situation either. Mainly it's because of a high torque on the bolts, plus repeated heat cycles. I didn't notice any use of an anti-seize compound on them.
I may post another follow-up post at a later time when I reassemble everything. Just dont get in a hurry if you ever have to do this and make sure you have all the necessary tools. When I reassemble stuff, I'll make another post but that isn't happening for a while especially since I have to order new bolts. I do intend to use a small amount of anti-seize compound on all of the bolts I had problems with.
Don't make the same mistakes I did