Topic: Terry's Effing F2, return of the prodigal SOHC4?

[Trevor from Warragul]

You have a sickness...   

[Terry in Australia]

Ha ha, you're right Trevor, and I know I should stop, but, well, I've had a K0 engine sitting around for years, so it'll be wonderful to marry them together and have a rolling K0, even if it just sits, unfinished, for years. The good thing is Honda isn't making any more of them, so it is an investment, of sorts.........

[PeWe]

There are lots of videos when searching on braze fuel tank.

Your tank has no old wonderful original paint to save anyway.
Make sure that there are no fumes left

[andy750]

I can offer that I had a K4 tank rust out from the outside -> in due to neglect and moisture being held by the stock trim along the bottom of the tank.

+1 thats how my K4 tank rusted out as well. How did you fix it Jeff?

[Terry in Australia]

There are lots of videos when searching on braze fuel tank.

Your tank has no old wonderful original paint to save anyway.
Make sure that there are no fumes left

Thanks Per, I've brazed several fuel tanks over the years, sometimes with great success, sometimes not so successful. I have Oxy/Acetylene, MIG, ARC, and TIG welders here, but I don't think that's the answer, because to do it properly I'd have to remove the spotwelds holding the badge mounting strips in place, and then manufacture a new section underneath, weld/braze/solder the new section in, make a new badge mounting strip, use a lot of filler to hide the new section before I paint it, and still need to use a liner to make sure there are no other pinholes to cause me some grief. The tank liner and some JB weld will do the job, with a lot less effort.

[RAFster122s]

You can mix up baking soda and vinegar slowly in a tall glass and once it is mixed very gently you pour the gas into the tank. The CO2 being heavier than air displaces the oxygen. Don’t pour the baking soda and vinegar solution in the tank. Somewhere I saw a formula for calculating how much of each to mix for a specified volume and what sized container to use.
 It was pretty interesting but I forgot to book mark it.
Just fill it with Acetylene and run some lamp wire that is loosely twisted together and stick it inside the tank. Then when you are at the end of that 20M of cord 20 M away from the tank, plug that cord into the mains while watching the tank.
You won’t have a small hole to repair then! I assure you that will be a fact!

[Terry in Australia]

You can mix up baking soda and vinegar slowly in a tall glass and once it is mixed very gently you pour the gas into the tank. The CO2 being heavier than air displaces the oxygen. Don’t pour the baking soda and vinegar solution in the tank. Somewhere I saw a formula for calculating how much of each to mix for a specified volume and what sized container to use.
 It was pretty interesting but I forgot to book mark it.
Just fill it with Acetylene and run some lamp wire that is loosely twisted together and stick it inside the tank. Then when you are at the end of that 20M of cord 20 M away from the tank, plug that cord into the mains while watching the tank.
You won’t have a small hole to repair then! I assure you that will be a fact!

Ha ha, don't forget my military background David. Acetylene bombs are what we used at Sergeants Mess functions to liven the various theme nights,  before "Occupational health and Safety" fun police banned the practise. We'd fill large garbage bags with acetylene, insert a length of two core "WD-1TT" (or "Don Ten" for the Vietnam vets) communication switchboard wire with the two wires twitched together, and hook it up to a "77 set" or "25 set" (radio) battery, from a safe(ish, depending on how drunk we were) distance.

We blew several windows out of the mess one night, and had to pass the hat around to collect enough money to pay to have the glass replaced. It may well have contributed to my tinnitus, come to think of it..........    

[MauiK3]

You Aussies love to have fun!!

[bear]

You can mix up baking soda and vinegar slowly in a tall glass and once it is mixed very gently you pour the gas into the tank. The CO2 being heavier than air displaces the oxygen. Don’t pour the baking soda and vinegar solution in the tank. Somewhere I saw a formula for calculating how much of each to mix for a specified volume and what sized container to use.
 It was pretty interesting but I forgot to book mark it.
Just fill it with Acetylene and run some lamp wire that is loosely twisted together and stick it inside the tank. Then when you are at the end of that 20M of cord 20 M away from the tank, plug that cord into the mains while watching the tank.
You won’t have a small hole to repair then! I assure you that will be a fact!

Ha ha, don't forget my military background David. Acetylene bombs are what we used at Sergeants Mess functions to liven the various theme nights,  before "Occupational health and Safety" fun police banned the practise. We'd fill large garbage bags with acetylene, insert a length of two core "WD-1TT" (or "Don Ten" for the Vietnam vets) communication switchboard wire with the two wires twitched together, and hook it up to a "77 set" or "25 set" (radio) battery, from a safe(ish, depending on how drunk we were) distance.

We blew several windows out of the mess one night, and had to pass the hat around to collect enough money to pay to have the glass replaced. It may well have contributed to my tinnitus, come to think of it..........

While we're sharing " Fun things to do with acetylene bombs".

I spent a period of my life long long ago driving tow trucks around Maroubra and Botany in Sydney, before a series of incidents forced me to reassess some of my lifestyle choices. In the end I concluded that I was more of a Country Mouse rather than a City Mouse.

Anyho' if a competing towy was caught off his patch, the first warning was usually a tap on the shoulder ie; an acetylene bomb attached to his truck.

The Bomb consisted of a plastic 2ltr Coke bottle, spark plug, a length of wire (optional) and a bit of electrical tape.
We would wrap electrical tape around the plug thread, fill the bottle full of acetylene mix then jam the plug into the top of the bottle and wrap some more tap around the outside to seal it.
Then wait for the offending towey to park his truck up for the night, crawl under, remove a plug lead and attach it to the plug on the bottle.

The result was usually a very satisfying  bang and a bright flash.

If you wanted to be sure the bomb detonated as soon as the key was turned you attached the optional wire to earth the plug. Otherwise, quite often there would be a delay.

[spotty]

and lets not forget the old rally favourite - the Stones bomb - take one recently emptied Stones Green Ginger wine bottle, fill to one thrid with petrol, screw cap back on and loosen one third of a turn. place pointing upwards in the obligatory bonfire and stand back. the petrol will boil and force the cap off, the sudden release of pressure will allow the petrol to vaporise and result in a beautiful fireball about 30 foot high.

one word of warning though - don't use the same bottle more than three times, it tends to promote structural weakness in the glass, ie bottle goes boom sideways instead of upwards

[RAFster122s]

Wow! You guys can play rough! I always knew that about you blokes but confirmed it bear.

Check out this beautiful '75 CB550F that a fellow Aussie up in Adelaide has finished recently. In four months no less! Gorgeous work.
https://m.facebook.com/paul.maccini.71/posts/pcb.773332629909529/?photo_id=1070247640101153&mds=%2Fphotos%2Fviewer%2F%3Fphotoset_token%3Dpcb.773332629909529%26photo%3D1070247640101153%26profileid%3D594774227%26source%3D48%26refid%3D18%26ref%3Dm_notif%26notif_t%3Dfeedback_reaction_generic%26_ft_%3Dqid.6879752806303550291%253Amf_story_key.773332629909529%253Agroup_id.185595442016587%253Atop_level_post_id.773332629909529%253Atl_objid.773332629909529%253Acontent_owner_id_new.100013477808871%253Apage_id.185595442016587%253Asrc.22%253Aphoto_attachments_list

[754]

 Can you screenshot it, Me not signing up for Facecrack..

[Terry in Australia]

Wow! You guys can play rough! I always knew that about you blokes but confirmed it bear.

Check out this beautiful '75 CB550F that a fellow Aussie up in Adelaide has finished recently. In four months no less! Gorgeous work.
https://m.facebook.com/paul.maccini.71/posts/pcb.773332629909529/?photo_id=1070247640101153&mds=%2Fphotos%2Fviewer%2F%3Fphotoset_token%3Dpcb.773332629909529%26photo%3D1070247640101153%26profileid%3D594774227%26source%3D48%26refid%3D18%26ref%3Dm_notif%26notif_t%3Dfeedback_reaction_generic%26_ft_%3Dqid.6879752806303550291%253Amf_story_key.773332629909529%253Agroup_id.185595442016587%253Atop_level_post_id.773332629909529%253Atl_objid.773332629909529%253Acontent_owner_id_new.100013477808871%253Apage_id.185595442016587%253Asrc.22%253Aphoto_attachments_list.[1070247566767827%252C1070247640101153%252C1070247703434480%252C1070247733434477%252C1070247766767807]%253Aphoto_id.1070247566767827%253Astory_location.6%253Astory_attachment_style.album%253Afilter.GroupStoriesByActivityEntQuery%253Atds_flgs.3%253Aott.AX9OfNJqjzl-u4e4%253Apage_insights.%257B%2522185595442016587%2522%253A%257B%2522page_id%2522%253A185595442016587%252C%2522page_id_type%2522%253A%2522group%2522%252C%2522actor_id%2522%253A100013477808871%252C%2522dm%2522%253A%257B%2522isShare%2522%253A0%252C%2522originalPostOwnerID%2522%253A0%257D%252C%2522psn%2522%253A%2522EntGroupMallPostCreationStory%2522%252C%2522post_context%2522%253A%257B%2522object_fbtype%2522%253A657%252C%2522publish_time%2522%253A1601801042%252C%2522story_name%2522%253A%2522EntGroupMallPostCreationStory%2522%252C%2522story_fbid%2522%253A[773332629909529]%257D%252C%2522role%2522%253A1%252C%2522sl%2522%253A6%257D%257D%26__tn__%3DEH-R%26cached_data%3Dfalse%26ftid%3D&mdp=1&mdf=1

Thanks David, that guy is a member of the SOHC750 FB group I'm in, it is a nice looking bike, but that link is broken, so I'm guessing it's been taken down now?

[RAFster122s]

Screenshots

[RAFster122s]

Screenshots 2

[Terry in Australia]

Oh, OK, that isn't the bike I was thinking of, the one I was talking about was a minty resto. Still nice though, not that I'm a big fan of the smaller SOHC4's, with one weakness, for the 350F, I restored one back to factory in 1996, and loved it, apart from the fact that it wouldn't pull a sick Indian out of his Teepee.........

[RAFster122s]

The captures don't do it justice, lots of hard work. Lightly polished covers on the motor and show award level paintwork. The seat has a color matched red piping swooping up separating the front and rear passenger areas and wrapping around the top to sides to the back of the seat. It follows the angle of the side cover before arching into the seat top. I couldn't believe he rebuilt that rotten seat pan.

[Terry in Australia]

Yep, looks great David, but I'm still not a fan, my mate Dobbo had a 550 back in the 1970's and I had a Suzuki GT750 3 cylinder two stroke, and I regularly kicked his arse, and covered him in a cloud of blue smoke. I wish I still had that Suzy smoke generator, but have no such feelings for the lesser SOHC4's.

[Trevor from Warragul]

not that I'm a big fan of the smaller SOHC4's, with one weakness, for the 350F, I restored one back to factory in 1996, and loved it, apart from the fact that it wouldn't pull a sick Indian out of his Teepee..

I agree.  They're a great bike for "puttering" around local roads, up to about 85 kmh, but pretty crap on the freeways.  What did you weigh in 1996?  You might find a 350F more tolerable now...   

[Terry in Australia]

not that I'm a big fan of the smaller SOHC4's, with one weakness, for the 350F, I restored one back to factory in 1996, and loved it, apart from the fact that it wouldn't pull a sick Indian out of his Teepee..

I agree.  They're a great bike for "puttering" around local roads, up to about 85 kmh, but pretty crap on the freeways.  What did you weigh in 1996?  You might find a 350F more tolerable now...   

Thanks Trevor, I think I'm about the same weight as I was then, the only difference is I was fit then......... I was offered a 400/4 for really cheap by a guy I bought some parts from in Seymour a few years ago, he sold me a very rough CB750K1 for 500 bucks and only wanted 200 for the 400/4, but sadly committed suicide on the anniversary of his daughters death in a car accident, so that was the end of that.

[Trevor from Warragul]

I've spoken to a few people who've owned both a 350F & 400F, and they all said the same thing - the 350F is a nice bike, but the 400F is much better.

[Terry in Australia]

Yep, if you like the look of the 400F, but it did nothing for me. When I was 16 I knew a girl who owned one, she was a little older than me, but would let me ride it with her on the back. Wow, that’s still a great memory, I need to find a red 400F and a pretty 18 year old to give it to.....

[Terry in Australia]

OK, so the F2 tank had a leak from behind the left hand side tank badge, so I bought a KBR tank sealant kit, which appears to be a very close cousin of the POR-15 kits that I've used before. Yesterday was a nice warm day, after a week of sh1t weather, so I got stuck in. First job was to use a strong degreaser that I mixed 50/50 with boiling water after sealing the petcock with a plastic disc and the OEM O ring, some "One Hundred Mile an Hour" tape to seal the leak around the badge holes, and on the other side too, just in case there were more pin holes to come.

I used the OEM fuel cap to seal the tank, then gave it a good swishing for 20 minutes or so, then dumped it out. It wasn't real bad, so I kept it for the K0 wrinkle tank that's on it's way.

F2 GPZ Saturday 10 Oct 2020 3 by Terry Prendergast, on Flickr

F2 GPZ Saturday 10 Oct 2020 1 by Terry Prendergast, on Flickr

There was a litre of phosphoric acid (dyed a fetching shade of blue) in the kit, so after rinsing and drying the tank with my heat gun after the degreasing, I tipped the acid in and gave it another good swishing. As I'd suspected, there was very little rust on the inside of the tank, and the acid came out nice and clean, so once again I saved it, if I need to do another tank I've got a can of POR-15 from a kit I bought ages ago, so I can do another tank if I need to. Once again, it's important to flush all of the acid out and dry the tank completely, before tipping in the liner. When I flushed it out, I discovered more holes under the badge mounting plate than I'd originally seen, but had suspected.

F2 GPZ Saturday 10 Oct 2020 9h by Terry Prendergast, on Flickr

Anyway, I stuck my heat gun back into the tank and mowed the lawn to kill time while it was drying out. I then had to let it cool for an hour or so so as not to cure the liner too quickly. I replaced the tape and poured the liner in, and this time used more tape to seal the fuel cap hole, I learned the hard way not to use the cap once before, when the sealer blocked the vent hole in my K2 tank and my beautiful blue K2 BOTM winner conked out every few hundred yards or so until I realised my error. I then spent 4 hours rotating the tank every 15 minutes.......

F2 GPZ Saturday 10 Oct 2020 9i by Terry Prendergast, on Flickr

This morning, because the tank was completely sealed, the sealant was still liquid, so I tipped the tank over so all the excess would move to the petcock side, then I put it on a cardboard box with rags and shop towel inside, and drained off the excess. You don't want this stuff pooling in your tank as if it's too thick, it won't dry properly, and you'll end up with sealant in your carbs, which is not a good thing. The idea was to let it all drain into the box and dry, then just throw it in the trash. Of course, Murphy's Law ("Anything that can go wrong will go wrong") stepped in, and the box leaked sealant all over my driveway, so I'll have a mess to clean up tomorrow, once I remove all the extra rags I used to mop it up.

K0 F2 GPZ Sun 11 Oct 2020 1 by Terry Prendergast, on Flickr

I also did more autopsy work on the GPZ1100 engine, but it's getting late, and so I'll bore your pants off about that tomorrow.

[RAFster122s]

Terry, how are you going to deal with the metal behind the band of steel strap beneath the badge? It hasn't had the rust removed and you haven't addressed any rust metal beneath that strap. What is to stop that rust from the outside continuing?

[Terry in Australia]

Thanks David, in fact I have addressed the rust behind the strap, I brushes phosphoric acid in there in the days leading up to the weekend and agitated it as best I could with a stainless steel brush, so with the added benefit of the tape catching and holding the phosphoric acid from the kit until I removed it to flush the tank, that area should be as clean as the inside of the tank.

I haven't removed the fresh piece of tape I put on before I tipped the sealer in yet, but I'm going to check to see if any flowed in behind the badge hole plate, but if not I prepared the tank before I started by dinging in the area around the obvious holes with the ball end of my ballpein hammer, so I can tip the tank on it's side and fill the whole badge area with JB Weld, except for the two holes for the badge themselves.

The tank is curing nicely inside after 24 hours removing the seals on the filler and petcock holes, so I've put it in my industrial oven set at 40 deg C (an average summers day here in Oz) and when I finish up work this afternoon I'll remove the tape, and mix up some JB Weld. I'd ordered some paint that I thought was close in colour to the blue sidecover on it at the moment, but then I discovered that it was actually a black bike (rare here in Oz, and probably not my bike, unless someone did a tank swap) so had decided to paint it black again, then today the blue paint arrived, so I'll have to think about it. Decisions, decisions........