1990 VFR750 with a familiar story... Petcock leaking and it’s not available. In my case, leaking from both the petcock body as well as through the outlet when the petcock was turned off. After reading a bunch on the forums I learned that it can be rebuilt. Should have got the kit from NRP but I decided to homebrew it. I thought I could add to the discussion here by providing details. I suggest the following Viton o-rings. Petcock to fuel tank: 24mm ID x 2mm wide, quantity one (not sure if still available as OEM? Disappeared from Honda p/n’s on revzilla, partzilla etc. No matter because others here called out the size so this one was easy, no need to pay for OEM) Side plate to petcock body: 29mm ID x 1.5mm wide, quantity one Internal seal: 7mm ID x 1.5mm wide, quantity one (one for US bikes with no reserve circuit, two if you have reserve). Shaft seal: 7mm ID x 2mm wide, quantity two **If turning your petcock “off” doesn’t stop the fuel flow to the outlet after you rebuild, you’ll also need a new spring about 0.9 wire thickness x 9.5mm OD x 10mm L. You might have to try different springs depending on how firm or soft the new spring is, but this is what worked for me. I got it from this kit: https://www.amazon.com/Compression-.../dp/B0BL7RYQ27/ref=sr_1_4?qid=1707004725&th=1 So that’s the short version! If you want pics and step by step keep reading!
I followed others’ recommendation from here to drill out the rivets and tap. There’s a Youtube video on this specific petcock here: I have access to a drill press so that made it easier to keep the drill bit centered but it was still a challenge. I mounted the petcock to a block of wood to hold the petcock for drilling and tapping. Didn’t want to drill out too much material when drilling out the rivets. Started with the drill press and ended up grinding them off with a Dremel. All the o-rings were toast. Two of the internal o-rings were molded like a figure 8. Not much corrosion. Disassembled and cleaned up the petcock.
You could install only one new internal o-ring to seal the ball when in the “off” position. I figure that steel ball may not need to rest on an o-ring when petcock is in the “on” position because it’s not sealing anything at that point. If you don’t want your ball to rest on metal when it's not in use, get two o-rings I used a 7mm ID x 2mm W o-ring for this. Getting that internal o-ring to seat was fiddly but with a little patience it worked out. You could probably go down a size on this internal o-ring, like 7mm ID x 1.5 mm W, to have less fuss getting it in.
Tight fit. I put a dab of oil on the the two new o-rings on the shaft. That made slipping them on easier and assembly easier.
Reassembled and was disappointed to find the petcock dribbled from the outlet when in the “off” position. I think this spring is old and tired. Replaced with a stiffer longer spring. It's a little harder to switch the petcock on/off but that seems to be what it needs to seal. Success! No leaks now!
nice write up, with the pictures. I watch the MotoRestoration guy on the youTube btw - he is a fellow Floridian. Peace
I have a Pingel petcock on my Kawasaki, I wonder if you could make one work on this application. I did have to enlarge the hole in the tank along with their base plate.
Thanks! Yes I wondered about alternatives in case my rebuild failed, but I could not find anything on a good replacement
Hi, I am Dennis, living in the Netherlands. Bumped into the same patcock leakage issue for my RC36 2 '96 VFR. Found like you all the part is not available anymore from Honda. I also looked at the rebuild video, and thought it will not fully solve my issue as the petcock filter in the tank was dried out and falling apart. So I got creative and designed an adapter plate, with the goal to 3D print it. I designed the adaptor plate for the still available Honda petcock for a CBR900RR of '93. Currently I am testing the printed part, and plan to post the design on https://www.thingiverse.com/ and maybe on the design part of Bambulabs when I think all flaws are designed out. This is the printed model I am currently testing This is my leak test setup on the garage floor: Thought to post this as a reply, also to find out if more VFR owners are interested in this solution direction.
This has been done. I bought one. I can't find the thread right now. But that's certainly not say there isn't room for another version that takes a different petcock solution. Cool.
I've seen that thread, but only after I was nearly finished with my design and ordered the Honda petcock.
The o-ring groove for against the tank is on the other side. This groove fits the original VFR petcock to tank o-ring. That o-ring is still available, contrary to the petcock.
Did you mean the groove in the first picture? That groove is for the o-ring on the CBR 900 RR petcock filter:
