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Discussion Starter #1 (Edited)
I've seen this question asked quite a few times, so I figured it wasn't a bad idea for people to post up what they've done to reduce the weights on their RC51s. I've got two SP2 RC51s, both 2002, one for street and one track. Wet weight of SP2 is 483, SP1 was 10lbs more, I think most weight diff was in exhaust, wheels, swingarm and subframe.

Street one is mostly stock, I figure I've taken 30lbs off, so it's 453 with the tank full. Main weight loss items are Jardine 2:1 exhaust (-15 lbs), speedcell-type battery (-6), 3-spoke CBR wheels (-1.5), Vortex clipons (-2), 520 conversion (-1) and aftermarket signals/bodywork/undertail (-3). Don't really want to drop anymore weight on it, but if I did then wheels or airbox would probably be the most cost effective.

Track bike should be at 420 with a full fuel tank, so most track days I'm riding around with the tank half full and weighing under 410. I haven't done everything, but dropping anymore weight is going to start getting seriously expensive, so here's the detailed list:

  • 2-1 full exhaust (-15)
  • Relocated speedcell-type battery (-7)
  • PVM 5Y forged aluminum wheels (-9)
  • CF airbox & intake (-7)
  • Vortex clipons (-2)
  • Track trim: no lights, signals, horn, ignition, mirrors, radiator fans, pass pegs, tool kit, kickstand, w/keyless gas cap (-16)
  • Pair/flapper (-2)
  • 520 conversion / aluminum rear sprocket / aftermarket rear rotor (-2.5)
  • Race subframe & wire harness (-2.5)
  • Race bodywork & superbike tail / foam seat (-5)
  • Scotts damper, PC3, frame sliders (+5)

What has everyone else done?
 

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So far:
Marchesini forged AL wheels
Akrapovic full system
Galfer rotors front and rear
Magnesium clip-ons
Carbon/kevlar fuel tank (when painting finished)
Fiberglass airbox
Turn-Tech battery
Pair/flapper mods
Titanium exhaust hangers
Titanium fasteners and link bolts
 

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Discussion Starter #3
So far:
Carbon/kevlar fuel tank (when painting finished)
Fiberglass airbox
Titanium fasteners and link bolts
Good stuff! Any ideas how much weight some of those items saved?

Are you running the Thorsten/TurnOne airbox? If so which carbon/kevlar fuel tank did you find to work with it? I've looked a couple places, but haven't really ever found too many Ti fasteners left over for the RC.
 

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Good stuff! Any ideas how much weight some of those items saved?

Are you running the Thorsten/TurnOne airbox? If so which carbon/kevlar fuel tank did you find to work with it? I've looked a couple places, but haven't really ever found too many Ti fasteners left over for the RC.
I have an ETI fuel cell I'm fitting to the bike.
It only weights 5 lbs by my scale (and I had a hard time believing it was that heavy).
And no, it does not fit the T-O airbox I have.

Rather than risk damaging the T-O airbox (since they're out of business), I'm instead fitting a copy of the Moriwaki airbox.

On a related note, anybody running a T-O snorkel on the street?
If so, did you have problems with headlight clearance?
Mine doesn't clear the headlight shells, so I'm reinstalling the OEM snorkel minus the internal flapper divider I removed.

As for Ti fasteners, Pro-Bolt has a reasonable selection.
Axle nut and bolt, caliper pad pins and bolts, linkage bolts, and the usual socket and flanged head bolts.
Mettec has some specialized bolts, such as cam cover bolts, linkage bolts, and such.
 

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On a related note, anybody running a T-O snorkel on the street?
If so, did you have problems with headlight clearance?
Mine doesn't clear the headlight shells, so I'm reinstalling the OEM snorkel minus the internal flapper divider I removed.
First gen snorkel was to wide for the headlights as you found out, second gen fit much better.

Also steering lock issues with the forks hitting the snorkel. Someone forced fit it but had problems with headlights starting to rub a hole in the snorkel.

I didn't like the fact you lost the upper fairing mounts either.

Check out the pics of a used first gen snorkel from a member at our friends at Speedzilla. You can see the future had you install the gen 1 snorkel.

http://www.speedzilla.com/forums/honda-sport-twins-classifieds/57081-fs-t1-carbon-snorkel-gen-1-a.html

Someone fabbed one out of aluminum that was petty cool but I'll be damned if I can remember where I saw it.
 

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Unfortunately, mine is gen 2 snorkel.
The lack upper cowl mounts would be no problem.
They can be fabricated with aluminum or carbon-fiber pieces and rivets.
Too bad someone can't injection mold a replacement performance snorkle.
While not as sexy as carbon-fiber, at least the dimensions would be consistent.
 

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I have an ETI fuel cell I'm fitting to the bike.
It only weights 5 lbs by my scale (and I had a hard time believing it was that heavy).
And no, it does not fit the T-O airbox I have.

Rather than risk damaging the T-O airbox (since they're out of business), I'm instead fitting a copy of the Moriwaki airbox.

On a related note, anybody running a T-O snorkel on the street?
If so, did you have problems with headlight clearance?
Mine doesn't clear the headlight shells, so I'm reinstalling the OEM snorkel minus the internal flapper divider I removed.

As for Ti fasteners, Pro-Bolt has a reasonable selection.
Axle nut and bolt, caliper pad pins and bolts, linkage bolts, and the usual socket and flanged head bolts.
Mettec has some specialized bolts, such as cam cover bolts, linkage bolts, and such.
I called ETI about getting a tank and they are telling me I need to cut about a 1/4 of inch off my Thorsten box. This means I will be cutting off the seal lip. What did you ever do with the sealing surface of your airbox to tank?
 

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I called ETI about getting a tank and they are telling me I need to cut about a 1/4 of inch off my Thorsten box. This means I will be cutting off the seal lip. What did you ever do with the sealing surface of your airbox to tank?
I'll be going around the problem by going with a different type of airbox instead.
It will be a copy of the Moriwaki airbox which doesn't use the tank to seal.

The ability to use the ETI fuel tank with combined weight loss offsets any slight decrease of airbox volume.
In conjunction with the lighter lithium battery, you're looking at least 15-18 lbs of polar mass lost.
 

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the seal is too keep dust out mostly. The 51 is so solid i would not worry about a little extra cool air going into the motor. i use a open style airbox and i have a filter to stop rocks and that is about it.

Back in the day many a RC30 racer propped the gas tank up a 1" or 2" to allow fresh unfiltered air in and i don't reacll reading or hearing about toasted motors or rings due to unfiltered air
 

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Unfortunately, mine is gen 2 snorkel.
The lack upper cowl mounts would be no problem.
They can be fabricated with aluminum or carbon-fiber pieces and rivets.
Too bad someone can't injection mold a replacement performance snorkle.
While not as sexy as carbon-fiber, at least the dimensions would be consistent.
don't worry. back in 2000 brain flow tested the OEM snorkel and OEM air filters and they flowed enough CFM's to run a big block chevy. the only thing the snorkel is good for is weight loss and looks(yes, i have one)
 

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the seal is too keep dust out mostly. The 51 is so solid i would not worry about a little extra cool air going into the motor. i use a open style airbox and i have a filter to stop rocks and that is about it.

Back in the day many a RC30 racer propped the gas tank up a 1" or 2" to allow fresh unfiltered air in and i don't reacll reading or hearing about toasted motors or rings due to unfiltered air
I can see this for racing as you'd expect the engines to be inspected/disassembled on a regular basis as they were pretty high stressed.
I recall watching a video and Colin Edwards offhand commented his engine needed major maintenance every 3500 Km.

However, here in Florida (which is a big sandbox) there's enough grit in the air from traffic that I'd never run unfiltered or partially filtered.
I'd gladly take the hit in performance over cylinder wear any day.
Instead, a performance gain from less weight would be more preferable from my standpoint.
 

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I can see this for racing as you'd expect the engines to be inspected/disassembled on a regular basis as they were pretty high stressed.
I recall watching a video and Colin Edwards offhand commented his engine needed major maintenance every 3500 Km.

However, here in Florida (which is a big sandbox) there's enough grit in the air from traffic that I'd never run unfiltered or partially filtered.
I'd gladly take the hit in performance over cylinder wear any day.
Instead, a performance gain from less weight would be more preferable from my standpoint.
prove it. you are speculating at best with no factual backing. I would like for you to show me one RC51 that has ever shown cyclinder wear from a thin or no filter and CE superbike does not constitute proof

i am not saying drive in sand only that a little fresh air even in FL will not damage the bike. these bikes go 60,000+ and have little or no valave adjustments and they have lasted over 100,000 miles i tend to doubt a little dusty air will ruin the sleeves until otherwise posted with fact.
 

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Pretty old thread I guess, but nevertheless.
Im about 444 lbs wet in street trim.
I've never weighed mine, but I have been curious what it's wet weight actually is.
Once I get it back together I'll try and locate some scales and satisfy my curiosity.
 
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