Carbon Fiber / Fiberglass Bodywork

[wolfeman28]

WARNING- LARGE PICTURE HEAVY THREAD



Not really attempting to 'peddle my wares' here, but figured some of you may find what I'm doing useful for DIY reasons, or are in need of other options for replacement.

My current tank on my RZ is still in useable condition, but I've never been happy with my rust hole repairs when I restored it. Also, the coating on the inside is starting to de-laminate after only a year. I recently got a small dent in the tank, and the repair resulted in the paint not flexing back into position properly. I'm to the point of just being done with the tank, no sense in putting new paint on it with the liner coming off and the possibility of pinholes still developing in the rusty areas inside.

I am going to prep the outside of the tank and make a mold. Since I'm putting the time into the tank mold, I'm just going to go all out and do the rest of my panels as well. The goal is to have near perfect molds of stock bodywork, and produce carbon fiber replicas. I'll have them painted and use those on the bike, and keep the originals in storage on the off chance I ever sell the bike.

Since I'll have the molds, I'm probably going to end up offering the parts for sale here and on ebay. Can't see me selling a lot of them, as most people will say they'll buy them beforehand, but never follow through (been there before with other products). But the molds will be here for use whenever someone is interested. Will also have the cheaper option of just fiberglass, but since I'm a one man show and not doing this to make money, they will probably end up being more than the options from Airtech (although I can guarantee a better surface finish and thicker product). Also of note should be that the carbon parts I'll be making are not for 'show' and will require painting and finish work. I can't stand visible carbon fiber parts to be honest, I think it's just as tacky as chrome all over cruisers. Most carbon fiber parts end up turning to shit in the presence of UV rays anyway, unless you spend the money on good UV resistant topcoat epoxy.

For the carbon parts, I'm going to be using a mix of Kevlar/Aramid and carbon fiber. Reason being is that carbon fiber on its own, specifically on the tank, has a chance of 2 bad things happening. In a crash, carbon fiber will have a tendency to take a big hit and reach a point of complete cracking failure faster than fibreglass would. Also, if the tank were to drag on the asphalt, a hole will develop rather quickly. Each of these scenarios increase the risk of fire, and I don't want that. So a few layers of carbon/kevlar hybrid fabric will decrease the possibility of a fire dramatically. I'm going to do the same on all the other panels as well to increase the abrasion resistance in case of a fall, which should make it easier to repair. Instead of having cracks to fix, it would end up being mostly just some filler and paint. I noticed this year when I was at the MotoGP race, that on some of the bikes you could visibly see that they use kevlar or something similar on panels. Probably explains why they hold up so well in crashes.

Going to be using ethanol resistant epoxy for the layup on the tank. I have a carbon fiber RS250 tank here that has held up for over a year now with ethanol/gasoline fuel and hasn't had any issues. Still going to take precautions like draining the tank during extended storage, good fuel filter, etc. Should be fine for oxygenated and race fuels too, but I'm not going to push it.

Tank will have stock style mounting points, stock style stainless bayonet filler neck, and stock style petcock mounting. The goal is to have a tank that just needs painted and is ready to go. The fuel filler neck will accept the stock gas cap, but will not be lockable. No big deal for me but just a thought. Stainless inserts will be used for the petcock bolt threads and will be anchored with no chance of coming out of the composite layers.

I've already come up with a solution for the side cover mounting pins (that go into the tank grommets). I found some nylon inserts that I should be able to set into the molds during layup. If those don't work there are some stainless inserts that may work.

I only have a solo seat, so that's what I'll be making a mold of. I won't be making brackets to sell if I end up selling the bodywork, as there are other options out there from other sellers. But the part I produce will be exact to the OEM solo seat panel. I may end up making solo seat pads as it's a pretty easy part with just a few fasteners, a backing panel, piece of foam, and small piece of vinyl cover. We shall see.

Going to make some right side crankcase covers as well, since those tend to take the brunt of damage on a right side fall. Specifically the oil/water pump cover, and the round insert with the Yamaha logo. Left side cover is a possibility as well, but with the amount of work that will need to go into it may not be a worthwhile adventure unless people want to buy them. Might make some of the covers that hide the coolant tank and YPVS motor as well.


That's it for now, just wanted to get a thread going on what I'll be doing. I'll use this thread as a build guide along the way and show pictures of my mold making process and the subsequent layup and vacuum bagging of the parts. I've ordered all needed supplies and dragged my vacuum pump and bagging materials out of storage, so should start making the molds in a week or 2. Need to add some clear coat to all my bodywork and get a nice flat buffed finish while waiting on the supplies to come in. Stay tuned.

[JonW]

Interesting post. Im really keen to see the process and how these come out. Good work.

[Hooligan]

I've considered some smaller CF parts for my LC but the prices are a bit dear.

[evan_calgary]

Do you have any prior experience with making carbon parts and specifically a gas tank? How many pieces are you planning to use for the mold and how do you intend to bond them? How will you seam the mold?

I see at least having to cut off the interior tank mounts to get the bottom mold and likely a 3 piece total. The fuel filler is a pain but not all that difficult to deal with.

I have quite a lot of experience with composites and a gas tank is definitely not a great first project. They are difficult to make. Kevlar/aramid also sucks to deal with and has poor bonding in comparison to Carbon or glass. Use a satin weave if you want to make things a bit easier on yourself.

[wolfeman28]

I have been building composite parts for over 20 years now covering cars, motorcycles, boats etc. So not my first rodeo :) I've designed and built my own carbon fiber PWC hulls from scratch all the way to a finished ski. Had to learn all on my own before Youtube was filled with videos on the subject (90% of which are complete hack nonsense, the other 10% being very good)

I've dealt with all types of re-enforcement fabrics before. Kevlar/aramid is a pain to work with yes, but the current hybrid weaves are not too bad as far as workability go. Hardest part with those fabrics is cutting them. Good resin coverage and ratio is important as well.

I have made tanks before that work fine. This one will have to be done in two sections, top/bottom, and then bonded. Top mold is going to be three piece, bottom mold two. No other way around it really if I want to retain all stock lines including the seam. Bonding will be done at the seam using the same epoxy used in the tank, along with Carbiso to make it more paste like. Worked on my prior 2 piece tank, so I'll stick with it. I can do the bottom in two pieces without having to remove the stock mounts. It's going to take some cleaver placement of filleting on the back side of them or else I'd never get the parts to release from the mold, but it can be done. As for the gas cap, it really is easy. I'll just be laying the first 2 layers of fabric down around the hole, filler neck goes in the hole, remaining layers on top of it. The filler neck I'm using has a nice flange on it which I will be drilling holes into, so the layers will anchor into it.

The key to getting a tank that won't eat itself to bits with modern fuel is really in the curing process. Simply letting a wet layup cure at room temperature is not enough. There have been papers written that show modern epoxies will be more resilient to ethanol when they are allowed to set at room temperature for several hours, followed by low heat post cure(I do 170deg F for 3 hours).

I'll show it all and explain further step by step as I go along with the project. Everyone can take the journey with me :p Something to add as I was thinking last night- I'm going to make a front fender mold and rear underbody mold as well. Will also be making a second mold for the upper fairing with no headlight hole, and a lower fairing piece with extended belly pan (should be large enough to meet most racing rules for fluid containment). I can only use what I have around here as guides, so it will be formed large enough to clear a set of JL pipes which should suffice for most others as well. As with all racing bodywork though, some fitting work my be required for your application.

[wolfeman28]

And in case anybody was wondering why CF and glass parts cost so much-

$428 so far in consumables and materials for just the molds (will need more to make the second upper and lower race fairing)
$624 estimated 12 hours labor for the molds @ $52/hr

I can probably get a good 10 parts per mold before they need reworked or redone. So you can start seeing where the cost of composites comes from. Not a cheap business, those mold and labor costs get pushed to the product price. Then add in the actual part materials, labor, and markup...

[Hooligan]

Oh I get why the CF stuff is so expensive but that doesn't make the price any easier to swallow.

[wolfeman28]

Oh I get why the CF stuff is so expensive but that doesn't make the price any easier to swallow.

Exactly. Only reason I'm even bothering is because I need the parts for myself to use, otherwise it just wouldn't be worth it. I may end up just making a few sets of complete parts for myself, and I can always put the molds up for sale on Ebay to recoup some of the cost I put into it.

[wolfeman28]

Bodywork I'm starting from.

[JonW]

Im with you on the costs, but I cant see how the labour is relevant if this is for you as this is 'hobby thing'. I've put countless hours into my builds and never consider what that element would be worth at the prevailing local mechanics / fabricators rate. I reckon if you make more than one (youve the mould made so why not etc) and sell a few to offset your costs you may well have those buyers cover the full cost of materials, and at that point I guess youve done ok, thats how Ive done it when Ive made more than one thing and sold it. Profit really only exists for businesses in this hobby. But, charge what you like, you never know what people will pay til you ask I guess.

Anyway, Im keen to see how you make the moulds and go about creating the panels. Im not a buyer, just a lookeyloo and keen to learn.

[wolfeman28]

Labor was pointed out just to show why production carbon fiber parts cost what they do.

[Questo vecchio rz]

Also of note should be that the carbon parts I'll be making are not for 'show' and will require painting and finish work. I can't stand visible carbon fiber parts to be honest, I think it's just as tacky as chrome all over cruisers. Most carbon fiber parts end up turning to shit in the presence of UV rays anyway, unless you spend the money on good UV resistant topcoat epoxy.

Amen, carbon fiber finish is SOoooo 90s. And for me does not even come close to the dated RZ style Apples to Oranges.
And yes, CF always fades...I have some nice CF stuff too...it's yellowed even the stuff that's never been mounted
Same goes for Anodized parts...looks great at 1st but rapidly diminishes, the only stuff that's ever held up is old Aerospace surplus. Everything is now done in China, and China sucks for quality 7 ways till next Sunday.

Have fun can't wait to follow your adventure

[JonW]

I always hate looking the under bonnet (trunk for some of you) of modified cars and see the hose fittings in racing pink and washy washy blue. Im all to aware of what those cost to buy and feel for the builder, even if it all looks so 90s now.

[kpke]

wolfeman28, the informative and knowledgeable posts you have made are great.

I will be following this with interest.

Some folks with piles of RZ projects may be interested in some of your handy work…

Whereabouts in the world are you located?

[Evans Ward]

Post #13- Jon, I agree with you 100%. Those anodized colors are so 90’s and trashy looking IMHO. Hate ‘em....