VF500 exhaust compatibility between models

I am in the process of building a VF500F2 hybrid: 84 bike with an 86 engine/carbs. All has been going well until I tried to fit the silencers. Now I have a few sets: 2 sets of originals in useable but rough, a pair of Marvins (Italian), and a pair of Motads (UK).

None were a straightforward fit. Mainly the rear mounting lug did not line up with the footrest plate mounting.

The Marvins (my preferred choice) eventually were coaxed into place but I found the centre stand fouled the pipe badly and forced it to hang really low.

The Motads had similar issues but again with a bit of brute force I got them on, but then found they fowled the pillion pegs when folded down!

I got 1 pair of orignals to fit, but had to push them further onto the collector box than normal to get the lug to line up….I then find that the centre stand does not locate in its recess and thus fowls the pipe and does not align with the bump stop rubber on the silencer.

So Im thinking collector box is the culprit. I was under the impression that these parts would be common to all VF500 models, but perhaps there is a difference, or possibly the frame holds the engine slightly further backward.

The collector box fitted perfectly onto the rear pipes and the 2 mounted bolts underneath lined up and screwed in fine, so its not like its a gash combination ox box to engine. It also has the correct part number stamping on the underside.

Anyhow, for the interim I am going to removed the centre stand which is the main issue at the moment, but any info on compatibility or pointers to the root cause would be appreciated.

 

The header pipes and collectors are the same on all 500F models.

Most aftermarket mufflers were not designed to retain the centerstand. Whether that was simply not having a stop or outright designed interference.

As to presumably stock mufflers not fitting correctly, don't know.

The engine / frame unit between years is not the culprit. Some people having reported issues fitting different years engine and frames, but I am pretty sure they are just dealing with weird manufacturing toleranace stack-ups, as I have mix-n-matched all 3 years without issue.