Resurrection #2 - 1990 RC30 - Speedzilla Motorcycle Message Forums
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post #1 of 5 (permalink) Old 03-17-2016, 07:18 PM Thread Starter
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Resurrection #2 - 1990 RC30

Come on, we have all done it.

Left pump gas in a bike too long and the magic chemical reactions that occur when the $hit that they sell for pump gas is left to its own devices after evaporation and the passage of time take place leaving behind that crusty brown residue, disabling petcocks, blocking fuel lines/filters, etc.

Even products that protect fuel systems (Stabil) cannot hold back this reaction if enough time passes. I know this because I made the mistake of thinking that the very small amount of residual gas (probably less than a cup total) that had been treated with Stabil would be fine long-term in my RC30 gas tank after I had put it away for storage years ago.

Many, many years ...

OK, like 8 years.

Yes, I had put the RC30 away for 8 years because replacement parts had become completely unavailable for it and I lived in fear of potential damage to bodywork, exhaust or god forbid that onobtainium OEM gas tank that could result from any number of situations that could arise from using the RC30 as a "driver".

However, after discussing it with Mrs. G-Man (AKA the Salisbury household CFO) we agreed that it was a shame to have the bike put up, not enjoying it. So late last year I started the process of resurrecting it for road use, vowing to never again leave it to collect dust under a cover.

So that being said I began the painful process of bringing a legacy V4 back to life in the face of the ongoing challenges of owning a limited run motorcycle entail.

1. Replaced tires since there is no way in Hell I'm putting the bike back on the road on rocks that have not seen the light of day since my daughter was in elementary school. I thank the motorcycles Gods that Harley-Davidson wanted an 18" rear sportbike tire for its V-Rod's otherwise RC30 owners would be SOL.

2. Fluid changes: Changed all the fluids and double checked I still had good compression and spark.

3. Carb rebuilds: If you own Honda V4's you either become an expert at them or find a mechanic you trust implicitly. I am the latter. V4 Jedi Masters reside at Lunsford's Northwest Honda/Ducati, having worked on all my V4's for more than 25 years. So once I had the bodywork off the RC30 I deliver it to Chi/Corky to lay healing hands on it yet again. After tearing them down and sourcing x-over tube O-rings and carb needle seats from the UK (no love from American Honda of course) the amazing sounds of gear driven cams is reverberating once again, even if being fed by a hanging gas bottle.

4. Fuel system damage: I've grown to really despise pump gas with ethanol. Despise is not really strong enough a word for it. I hate that $hit. If you keep gas in a carb'ed motorcycle for any length of time without treating the fuel you will grow to share my feelings for it as well. Stabil will delay the fuel from breaking down and reduce the likelihood of corrosion damage associated with ethanol/additives but it will not protect you forever.

I had put the RC30 tank away with residual gas left in the tank and even though the fuel had been treated I ended up with a petcock that is completely blocked (did I mention there are no replacement petcocks available for RC30's nor can you get OEM diaphragm/o-ring kits for them?) and a gas cap that would not unlock/open. I'm waiting on replacement O-rings from a top-secret source to rebuild the petcock so I focused my attention to trying to get the fuel tank locking gas cap open. So, the key inserts but will not turn (yes, it is the correct key).

WD40 Penetrant and PBlaster down the lock cylinder does nada, even after soaking for a weekend. After taking tank to a locksmith to confirm there is no cylinder damage I determine that the lock assembly is not the issue. The issue is that the lock latch arms are seized and any amount of force applied to the key to force them open will most likely result in broken key and a very pissed off G-Man (did I mention that there are no OEM locksets or locking gas cap assemblies available for the RC30?).

The great oracle Google says to try filling the fuel tank full of Diet Coke (phosperic acid) and let soak for 2-3 days. Strike 1.

The great oracle then suggests filling tank with white vinegar (acedic acid) for similar duration soak. Strike 2.

Soak the tank in CLR? Not a good suggestion based on possible damage to the aluminum tank and/or the latch assemblies.

So now I'm getting concerned that I might have to cut the tank bottom to access the latches from inside to bust them loose but that is going to be a last resort. Then it occurs to me why can't I soak the tank in Berryman Carb Parts Cleaner? It's safe for aluminum and the pot metal that the cap assembly is made of. $18 for 96oz from Walmart and I only have to buy enough to submerge that gas cap assembly when the tank is placed upside down. Put 3 paint can's worth into the tank, invert and leave overnight.


Next day, I try the key in the lock, gently working it back and forth and I feel it start to give. 2 minutes later I have the cap open and able to remove:

I was also able to finally get the broken fuel filter screen remains out from the tank (did I mention also not available from Honda?).

I will say that that after exposing the aluminum tank interior to phosperic acid, acedic acid and parts cleaner for more than a week combined that I quite possibly now have the cleanest RC30 fuel tank interior in existence.

So important lesson is if you are going to put any fuel system components up for longer than 30 days that have contained pump gas with ethanol is to be sure and completely drain/dry the tank/carbs/lines. All of it. PERIOD.

Additionally, if at all possible run ethanol-free gas in your classics. Check your local marinas or aviation fuel depots for ethanol free pumps since federal laws prohibit the sale of ethanol free fuel within 50 miles of certain size metropolitan areas. I get mine from a boat marina located off the southeast tip of Lake Livingston, about 40 miles from my home, and pay about $2.39/gallon while the 10% ethanol 87 octane pump gas sells for $1.69. Check, Ethanol-free gas stations in the U.S. and Canada , for ethanol free pump/seller locations near you.

Next steps? Waiting on 2nd set of RC30 bodywork that will be used for road duty to make it back from the RC30 guru Jim Granger (located in Encino, Ca.).
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post #2 of 5 (permalink) Old 03-17-2016, 07:22 PM Thread Starter
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After getting the gas tank and fuel petcock apart it had to be sent out to RC30 guru Jim Granger for a rebuild (as he is the only source in the world for the petcock internal parts):

Once the petcock had been revived and the RC30 had received requisite fresh filters, fluids, tires etc. and making sure all the soft parts are road-worthy the RC30 went on the dyno to baseline the jetting after putting the bike back to stock exhaust.

Bike is still a little rich from 4000-8000 RPM so I need to drop the needles a couple positions but its making 96HP at 11k.

Video of dyno pulls:

Many, many thanks to friends and staff at Bob Lunsford's Northwest Honda for their continued support and unlimited access to their Dynojet 250 dyno.
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post #3 of 5 (permalink) Old 03-17-2016, 07:25 PM Thread Starter
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After spending way too much time dropping the needles (note to self, make life much, muich easier and unstrap from dyno to swap needles) this is the result:

Red run is post dropping needles. Dropping the needles two positions improved A/F and HP significantly from 4k-6.5k and was on par with the previous run with the exception of a dip at around 8300 RPM. Interesting thing is A/F was spot on at 13 when the dip occurred. Since the needles are at 2nd to highest position any more tuning is going to be limited without swapping jets out and which is going to be too drastic a change in either direction.
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post #4 of 5 (permalink) Old 03-17-2016, 07:28 PM Thread Starter
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So after resolving the jetting the RC30 is now home.

Spent a couple hours giving it a thorough cleaning prior to mounting the gas tank and front fairing/mirror mounting bracket for the last time.

While I'm in search of the unobtanium license plate bracket stay that mounts to the fender for the OEM license plate frame I needed a legal license plate bracket with light that did not require me to drill holes in the unobtainable rear undertray/fender.

Picked up one of the metal license plate frames with LED light strip mounted in the top portion of the frame (google Radiantz License Plate frame off Amazon, $30). This is actually fairly nice quality metal frame and once I encased the power and ground wires with some wireskin ends up looking fairly OEM. Soldered in some OEM bullet connectors from a trashed turn signal and the lighted frame was ready to mount.

Rummaged through several parts spare boxes and found what I believe is an OEM license plate bracket from my CBR1100xx that was removed when I installed hard bag mounts. The spacing in the mounting bolts on the bracket match the RC30 fender holes perfectly.

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post #5 of 5 (permalink) Old 04-14-2016, 10:22 PM
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I have a bunch of parts still for the RC30 including a petcock and stuff if you need.

Good to hear you still have that bike

shameless plug but you might know somebody looking for my RC30 if the price is right or a good trade

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1990 RC30
2001 RC51
2006 R1
2002 TL1000r
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