yes, these old pictures and films are wonderful, i really enjoyed Wayne's film of racing in his area back in the day when we  were young.

Wayne, thanks for sharing such a wonderful movie.

hmm...  What an era to grow up in...

Ash, thanks for your great reply and your experience working in that industry.  looking forward to what more you share on the topic.  i am glad the caswells is all gone.  i'm sure it's a good product, i have great results in the little Yamaha tank i did at least 10 years ago, but i would need at least one compelling reason why i should use the stuff again.

Steve,
Sealeater which I used in my CBX tank is Dichloromethane according to the label.

From what I can tell it appears to soften the sealant in my tank (white in appearance) but not actually dissolve it. I suspect that were the tank to be brim full, and left for an extended time period, it would probably remove all of the liner. A CBX tank full of Sealeater would cost approx. £500, hence why I only tried a 1 litre initially.

Quite a novel you produced regarding sealants, etc - interesting reading.

I would absolutely agree that preparation is everything, and given the time it takes perhaps no wonder that few "professionally applied" liners actually last.
Also that lining a tank is last resort gives the numerous ways of, and products for, de-rusting of tanks.

Unfortunately the only other tank I have that has been lined is that on #302, but the when, how, why, etc is another story!

Agree with KP, stunning backdrop; perhaps one I have seen?

Chris R.

Chris R.

thanks for your reply, Chris.   Dichloromethane is methylene chloride, so we're using the same stuff.  appears the caswells is    s  l  o  w  l  y  going into solution with the methylene chloride; at  the rate the caswells is going into solution, i am expecting a month at least  before the stuff might be able to be poured out. kind of the shits if the stuff won't come out without breaking it up as there is no way to get to "the bag."

Hi Chris,

Thank you for your as always thoughtful posts and your experience dealing with the sealer you have in your tank.  i suspect "Fertan" tank sealer is a product used in Europe, so wonder what made in america product would be same or similar.  i also note, unfortunately, Fertan is not sipped to usa.  so....  i wonder what the active ingredients Fertan in UK is made up of......  doing a quick google search, Fertan in usa is a rust remover.  Chris, anything on your Fertan container give ingredients?

i've prepped and sealed around 50 tanks in my time, most of them when i worked for a local motorcycle repair shop, used different sealer products on 5-10 of my tanks.  without exception, i believe all sealer products are good.  in the case of the probably 25 sealer failures i have seen, without exception, is because inadequate prep was done prior to installing the sealer and inadequate prep is, without exception, due to lack of thoroughness and patience on the part of the individual doing the work.

This topic could entail a very long post on a number of different topics related to tank prep; i have neither the time or desire to do so. 

Despite all the garbage written on numerous websites by people who lack experience, critical thinking skills or are simply keyboard commandos off-gassing, there is no dark secret nor black magic to remove rust from a tank.  In my experience, what there is, is a number of very effective ways to remove rust from a motorcycle gas tank, i'll cover briefly at the end of this tale.

sealers such as kreem, red-kote and por-15 are all methyl ethyl ketone based and as such, mek or acetone does readily remove these liner products.

caswells is a 2 part epoxy and as such, mek will not touch it.  after i wrote the above thread, i did call caswells and they confirmed what i already at least thought correct; methylene chloride is supposed to remove caswells.  so, i ordered 1 gallon of methylene chloride which arrived yesterday and i now have fragments of caswells in a glass jar with the methylene chloride, which, after 36 hours does not appear to put much, if any, of a "dent" in softening or bringing the caswells into solution with methylene chloride.

this being said, feeling desperate that methylene choride does not seem to affect caswells, earlier today i purchased one gallon of a paint stripper product available in america, "zip-strip" (knowing it also contained methylene chloride).  like i said, i am feeling desperate, but my past experience told me it is highly effective removing rock-hard dried gas in gas tanks, so what the hay, huh?  i've used zip-strip numerous times in the past for paint removal.  reading the back of the can, the active ingredients of zip-strip are methylene chloride, methanol and mineral spirits.   subsequently, i added equal parts of zip-strip to the jar with methylene chloride and caswells fragments.  i should think 24 hours should be sufficient time to see if this brew takes caswells into solution.

well.....  this is longer than i wanted to take writing but i will share a few bits of my experience using different sealer products.

kreem:  if a tank has pinholes, kreem is what i suggest using.  semi-viscous out of the can and as it is applied, the mek will evaporate off so a thicker coat can be applied and need be is readily thinned by adding a very small amount of mek.  application of kreem is not readily affected by temperature variations, 10 or slightly more degrees (F) one way or the other will not adversely affect viscosity. dries semi-white opaque depending non how thick you apply the coat(s).  a coating of kreem can be as thick or thin as you prefer; from opaque white to white.  i have seen kreem jobs that look as good 20 years after application as if they were the day before. personally, with tanks i've applied kreem to,  i've not yet experienced failure with kreem.  never sets up hard, always has a bit of elasticity.

red-kote: other than being clear and red and slightly less viscous than kreem, otherwise seems to respond same as kreem.  leaves a clear red coat which can be made thicker with prolonged rotation, but not as readily thicker coat as kreem.  (whether kreem or red-kote, do not leave excessive pools of it on bottom of tank; drain as well as possible.  if you feel there the coat is excessive, add a small amount of mek to thin so you can pour out excess).  antique motorcycle guys swear by red-kote; they use it in 60-110 year old tanks.  i applied the stuff to my pair of 1927 gas tanks; first time i've ever used the stuff, but i followed in the footsteps of those more experienced than i who report good results.  never sets up hard, always has a bit of elasticity.

por-15: pretty runny, definitely no like water and definitely less viscous the the above two sealers.  is more sensitive to temperature variations affecting viscosity and without exception leaves a thin silvery sort of hammerloid-appearing coat.  if you have multiple small pin holes you want to seal, use por-15 at your own risk for failing to seal holes.  i used por-15 on 2157 tank, after 9 years it look as good as the day i applied it.  sets up hard.

caswells:  clear, so really dificult to see if all parts of tank are coated.  very sensitive to even 5 degree temp variations so within these temp ranges can be nearly runny as water and thick as syrup.  because caswells is a 2 part epoxy, it begins setting up within 10-20  minutes (depending on ambient temperature) and if you wait too long, the excess becomes increasingly difficult to drain out (i suspect because when the 2 parts are mixed, a sort of catalytic reaction begins).  once set up, hard as glass.  it has been 14+ years ago i applied caswells to my little yamaha tank, looks as good as the day i put it in.

what i have learned about manufacturer's prep and application instructions:  they only give the basic or general idea for tank prep; none consider severity of tank interior and other factors.  caswells instructions to "place a hand full of sheet rock screws" to remove rust is  and "to plug outlet ports with putty or Play-Doh" IS SIMPLY RIDICULOUS. actually, their advice is simply f---ing ridiculous.  otherwise, sealer manufacturer's prep and application instructions are woefully vague and woefully inadequate.

based on my experience, i firmly believe everyone of these products are excellent ONLY IF PREP IS PERFECT.  what users fail to realize when it comes to prep, there are many ways in which prep can be carried out.  I ONLY USE A LINER WHEN I BELIEVE THE INTEGRITY (STRUCTURE) OF THE TANK IS COMPROMISED.  otherwise after i have rust out, i keep bare steel.  regardless, i always keep my tanks filled with gas and in bikes i have in long term storage, i oil the inside.  mind you, i live in semi-arid conditions, so i don't have the humid conditions others must contend with.

as far as blaming ethanol gas on liner failures, myself i believe that is a convenient excuse to not account for tank prep appropriate to the needs of each particular tank.  in other words, poor tank prep causes liner failure, not ethanol gas.  i've personally seen (and heard of) many a lined tank containing ethanol gas hold up for years without a problem.

for those considering using any tank liner product, I CANNOT STRESS ENOUGH THOROUGH TANK PREP.  there are quite a number of different ways to prep a tank and the reason a tank needs prepped is usually because the inside of the tank is rusty.  regardless, the last thing i do before the final DRYING rinse, is i always rotate (sometimes 2, 3, 4 and even 5 cycles) the tank in an old clothes dryer i have; the tank being rotated containing twenty-five 1/2" nuts and twenty-five 9/16" nuts to dislodge anything my tank prepped may have failed to. (DO NOT use a nut larger than 9/16" !)

i will touch only briefly on rust removal and tank prep procedures i have used:

1. 3% phosphoric acid solution as comes with kreem, red-kote, por-15. 

2.  reverse electrolysis

3.  molasses

4. "wood," i.e., oxalic acid

regardless, i always do the rotate the tank with nuts in it routine.  (i used to try to shake the tank by hand and all that did was wear me out.)

when it comes to tank prep and especially installing the liner, have your step by step plan all laid out.  have effective fool proof ways to block openings.  once i am satisfied the sealer is somewhat set i open up all orifices and put a fan to the tank to help circulate air through tank.  and i check routinely to make sure any residual sealer is not pooling; again i rotate.

in closing, depending on the tank, prep, depending on approach, can take anywhere between 5 and 25 hours spread over usually no less than 3 days and up to 6 weeks.  good tank prep is tedious, time consuming and requires near if not continual attention, as well as  patience, persistence and perseverance.  good tank prep requires a well thought out step-by-step process before starting the process; especially the lining process.  pity anyone who is dealing with a lovely painted tank....... 

well.......  it's been over 2-1/2 hours the caswells has been soaking in my methylene chloride/zip-strip brew since i started writing this novel.  hard to tell if "the brew" is making a difference.  shall report back.

What is the jerk who said or wrote that the CB750 are wriggling like sausages ?
Thanks you Steve for sharing

Gerard, great to hear from you.  one of the things i noticed on the bike in the foreground, the rear shocks to not appear stock, so it makes me wonder if they are aftermarket.  in my own humble experience, i remember my K2 wallowing through a turn and i remember  4779 not ever wallowing.  i'm pretty sure i never had either 4779 or the K2 leaned over as far as these guys have these bikes leaned into the turn.   When i experienced wallowing with my K2 i do not remember going through the turn at any excessively high speed, was just normal driving.  i honestly don't know if the DeCarbon shocks fitted to sandcast bikes were any much better than the Showa's on later bikes, i may (please) stand corrected, the thing that distinguished the DeCarbon's, they were charged with nitrogen gas to help keep the oil in the shock from over heating.....?  Although the shocks on K1's appeared same as or at least similar to the DeCarbon's, the K1's did not have 7 springs exposed and did not have a DeCarbon sticker on them.  Back to my experience owning a K2, between the wallowing, the mufflers showing rot, and significantly slower than 4779, i became disillusioned with the K2 and traded it in on a brand new black 1974 Norton Commando Roadster i rode trouble free for 20,000 miles and never had one regret.  Other than the technology of an sohc transverse 4 on a production motorcycle and not having to routinely make ignition points adjustments and check timing on the Honda 750, in my humble experience, for sheer riding pleasure, the  Commando was the superior motorcycle.  in terms of riding performance, what the Commando lacked in horsepower, it made up in being around roughly 75 pounds lighter and the Commando's handling is nimble, quick, and light in contrast to the Honda 750.  For those of you have been on the forum since the beginning, you will perhaps remember my story of beating Norm Mathis' red K1.  Norm and i "ran off" his K1 and my Commando; i could beat Norm fairly consistently.  Once in a while he could pull past me and and stay ahead, but more often than not the lesser weight of the Commando usually gave me the advantage.   

fwiw, specifications of the Commando and CB750, respectively:  dry weight 422 vs. 480 pounds; wet with full tank of fuel, 450 vs. 513 pounds.  Horsepower; 59 vs. 68.  What the CB750 had in higher engine rpm's, the Commando made up in torque; 56 ft.lbs at 6,000 rpm vs. 44 ft.lbs at 7,000 rpm.  max rpm's 7,200 vs. 8,500.

it was during the summer of 1975, i attended road races in Aspen, Colorado; transverse 4's and 2-stroke triples were in force on the tracks.  there were only a few British twins racing.  i distinctly remember the 4's and triple's far outdistancing the British bikes in the straights, only for a few of the British bikes to close the distance to the Japanese bikes in the turns and then be out-accelerated time and again.  i also remember seeing some of the 4's and triple's doing some really heavy wallowing through the turns and feeling glad i had traded the K2 for the Commando.