Gregory Bender

Rear fender installation

Moto Guzzi V700, V7 Special, Ambassador, 850 GT, 850 GT California, Eldorado, and 850 California Police models


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When I disassembled my Ambassador, the rear fender came apart just fine (at least as far as I can remember - things always seem to come apart better than they go back together). But when it came time to put the rear fender back into the frame, I couldn't believe how tight it was. I just couldn't get the bolt holes to line up. Perhaps the bead/sand blasting that was done to it before painting had created a slightly larger arc. Or, maybe the fender was that tight from the get go. At any rate, it was tight enough for me to stand back and take a look at my frame to see if it was bent. It didn't appear so.

I ended up calling John Schwartz for some advice. He assured me that my problem was not uncommon. He had encountered very stubborn rear fenders on loop frames before, too. The long and the short of it is that getting the rear fender mounted back into the bike can be difficult. Using some of John's advice and some of my own ideas, I eventually got the fender mounted and in place. Here is what worked for me:

This all sounds nice and systematic...but, as you can well imagine, it wasn't. Good luck.

Improving the fit of the rear fender

I've never been happy with the fit of my rear fender. It takes a lot of effort to get it installed, and all the flexing forces the sides to bow out and rub on the side of the frame. The problem hasn't been visible, but it has annoyed me nonetheless. My rear fender had to be repaired and repainted after I got rear-ended by an automobile in . I figured this was the perfect time to see if I could solve this problem once and for all.

I suspected that the rear loop of frame had gotten bent downward slightly from too much weight sitting on the pillion and/or attached to a rear luggage rack (before I owned the motorcycle). To this end, I attempted to bend the top loop upward. I rigged up a leverage system using 34 inch steel pipe and T unions. I had a lot of leverage (close to 5 ft) and I didn't move it a bit. That rear loop is a lot stouter than I originally thought. I mentioned the idea of the rear loop bending to Mark Etheridge of Moto Guzzi Classics and he laughed. Mark also confirmed to me that many/most of the rear fenders he has installed have too tight of a fit.

What to do?

I knew I could elongate the slots in the fender for the rear mount. But I couldn't do much of anything there without the slots then showing beneath the corresponding mount in the frame. Therefore, I didn't modify these slots at all.

I started up front enlarging the reinforced mounting holes in the fender to 38 inch using a hand drill. This helped significantly, especially with the right side front mount. But the left side front mount was still very tight and still wanted to flex the fender too much.

Next, I lengthened the front slot in the battery tray on the left side. I used a round file for this. I'm not sure how much material I removed, probably around 18 inch but maybe a bit more. This helped with the fitment, but the left side was still too tight.

Finally, I enlarged the left reinforced mounting hole in the fender to 716 inch using a hand drill. With this huge hole in the fender, I was able to fit the fender without all the nasty flexing. 716 inch is quite large and I don't think I'd want to go any bigger than that (I was a lot more comfortable with 38 inch holes). I used thick fender washers on the inside to help distribute the clamping force.

This the first time I've mounted this rear fender without the sides buckling under the pressure and then rubbing on the frame. Thank goodness. Worth the effort - to me, anyway.


Please take care when making modifications such as these. It is very easy to remove too much material and introduce another problem, such as:

  • elongated holes now visible behind the rear mount
  • the fender touching the horizontal portion of the battery tray
  • no longer having sufficient space through which to route wires
  • the tool boxes being positioned too far forward and hitting the frame
  • having to enlarge the holes in order to mount the tool boxes

In short, go slow and check your work carefully.