fastbroshi

So it looks like I misread the parts listing and if part # 16952-MBB-003 (both the Blackbird and Superhawk filter; you're correct Captain) was available.  The filter looks like it will fit.  

I just ordered a vendor on ebay's last one.  Fingers crossed it fits ok.  

After some more looking, it appears the '97-'98 Blackbird petcocks have an identical base to the VFR's.  The outside is much different, but compare the base in this link to the base of my petcock above:

https://www.partzilla.com/product/honda/16950-MBB-642?gad=1&gclid=Cj0KCQiAr8eqBhD3ARIsAIe-buMLcc0849cy69Jp2TGBxd2vogww_dy_pZGjRKI8oVmf-6V9_jvsQKoaAlwaEALw_wcB

I'm convinced the filter for this petcock would work, but I can't find a separate one just yet and I don't want to spend over $200 to test my theory.

Does anyone have a spare carb'ed Blackbird petcock just lying around?

On 11/11/2023 at 1:18 AM, Dutchy said:

On the 4th gen (never owned a 3rd gen) this switch is located under the tank, so unlike the VF500F's (which is on the LHS of the tank and has ON//OFF/RES), you only switch the 4th Gen's to OFF if you want to remove the tank.

 

NRP in the UK sells

https://nrp-carbs.co.uk/shop/index.php?route=product/search&search=vfr750

 

The inlinle  "strainer" you could replace with an external filter, or leave it out altogether.

Dutchy, I will look at that petcock and verify if it interchanges.  If so Honda needs to update their parts diagram supercede #!

My current plan, if the VF500 version isn't viable, is to break off the remaining filter plastic, leaving just the base.  This appears that it will still seal when seated properly with a new o-ring.  I'm going to take some stainless pipes and cut them to length to mimic the height of the plastic filter's cylinders.  Cut windows in them and cover with stainless mesh, epoxy in place.  Mate the pipes to the plastic base with epoxy, being careful to not mount too deep and keeping total height in mind.  Cap the pipes with stainless plugs.  

  If I had a lathe I wouldn't have to use the original plastic base and just turn it out of stainless, drill two holes for the tubes, etc.  But I have no practical lathe experience either lol.

On 11/11/2023 at 9:12 AM, jefferson said:

Attack of the ethanol demons.

Precisely.  The bike hasn't had a full tank ran through it in over 5 years.

7 hours ago, JZH said:

The petcock is interesting.  I'm not 100% sure about the 4th gens, but Honda used the same petcock on all 3rd gens, whether they had the US-style "no reserve" or the ROW's remote reserve switch (but no low fuel light).  (The "MT4" on the strainer tube suggests that the part is the same across all 3rd and 4th gens, however.)  The difference at the petcock was in the knob used: the US-spec knob goes from OFF to ON, with RES being blocked. 

 

The difference between ON and RES is simply which inlet is directed to the petcock's output.  But that only works when the OEM fuel strainer tubes are fitted, which make the ON inlet effectively a couple of inches higher than the RES inlet within the fuel tank.  So, on non-US-Spec bikes, when the switch is ON and the fuel level drops to the level of the ON inlet on the strainer tube, the engine sputters--prompting the rider to turn the switch to RES (ideally in one swift move without breaking stride)--which then allows the RES inlet at the bottom of the tank feed the remaining fuel in the tank to the carbs.

 

US-spec bikes only use one of the inlets (the RES, which is the lower one), which means that if your OEM fuel strainer tube falls to bits all you really need to do is fit a strainer/mesh to the RES inlet on the petcock and you'll have "full US-spec" functionality again.  Or don't fit anything and rely on your fuel filter?  (Not what I would suggest!)

 

However, the petcock itself might be past its prime, but it can be rebuilt using common o-rings.  Drill out the two rivets and tap the holes for M4 (I think it was--whatever is smallest that allows threads to be tapped).  NRP in the UK sells dedicated rebuild kits, but any o-rings (which fit) can be used in a pinch.  Unlike earlier petcocks which use special-sized seals, this model only uses round ones.  With some trial and error, and a good selection of fuel-resistant o-rings in different sizes, you can rebuild these petcocks to again function perfectly.

 

Ciao,

JZH

Thankfully the o-rings appear to only seal the on/off knob's shaft.  Those are not leaking.  After I cleaned out all of the sulfur looking powder, I was able to verify it still seals properly when turned off and flows when on.

It appears this type of petcock was only used in the 3rd/4th gens, and it is no longer available from Honda.  Conveniently this style looks to be somewhat unique and doesn't look as if other types are readily adaptable.  I have some ideas, but I'd like to know what anyone else has tried.

I got one for my 4th gen adn loved how it diverted air off me at highway speed. Mine was defect free and was very clear, but oddly was dirty. And the fit was a little off, I had to dremel out one of the holes so it would fit right.

Okay, I'm following your explanation, but those bars pictured don't look to have any cant backwards. And what kind of bars are they? I couldn't figure out by your first post.

I agree that the stock suspension components for US-bound bikes should "fit" slightly heavier riders, but especially on bikes aimed at the sport-touring segment, designed to be ridden loaded with bags and/or 2-up.

But I also agree with George - suspension is one of those things you mod if necessary, and for most people isn't a barrier to buying a certain bike. I'm planning to mod my VFR's suspenders this off-season.

That's the thing, if you spoke to their engineers, you KNOW they'd recommend different spring rates for our continent. And cars don't apply here: apples and oranges. I think it comes down to a money thing. Honda doesn't change it because they don't have to. There's not enough squeaking coming from the wheel to get any grease.

Just got done reading the Fatty McGee thread here:

http://www.vfrdiscussion.com/forum/index.p...51678&st=30

There were some comments about how losing weight makes the bike handle better, inputs are more readily felt, etc. That got me thinking. The average American is let's say, 50lbs heavier than your typical Japanese or even Asian person. I'd venture to say this is Honda's biggest market, in Asia.

I have a hard time believing Honda won't fit uprated springs and such because of the logistics involved, but I think this is the case. Which is crazy when you think about all the man hours that goes into R&D for these bikes. How about more of a middle ground Honda? Why not set it up for 175lb rider instead of 150lb?

I'm sure the folks in the East love their Hondas and the way they ride, but isn't Honda concerned with what their customers think? I think the consensus is ALL of our bikes, even the 929s and 600RRs can use some suspension work, unless your a female and then you're more inline with the Asian males :biggrin:

Our market is obviously a lot smaller than the Asian one, but I don't think small enough to not warrant a different setup.

Thoughts? Talk amongst yourselves, discuss, discuss.

As Bill & Ted would say, EX-CEL-LENT!!