Author Topic: Terry's NEW Redneck CB750 rebuild. The "Swamp Rat". Too soon? Nah..........  (Read 48856 times)

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Offline Gurp

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I also have the largest selection of used CB750 clutch plates in the southern hemisphere.......... ;D

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slow Progress 74 cb550.

Poor boy chop 73 CB500 chop

Future project 77 Cb750 Amen Savior

Offline 754

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We can be your YouTube torMENTORS... lol.. :o
Maker of the WELDLESS 750 Frame Kit
dodogas99@gmail.com
Kelowna B.C.       Canada

My next bike will be a ..ANFOB.....

It's All part of the ADVENTURE...

73 836cc.. Green, had it for 3 decades!!
Lost quite a few CB 750's along the way

Offline Terry in Australia

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We can be your YouTube torMENTORS... lol.. :o

That's OK with me Frank, jump on and watch me fcuk something up, just remember to "Like" and "Subscribe"! ;D
I was feeling sorry for myself because I couldn't afford new bike boots, until I met a man with no legs.

So I said, "Hey mate, you haven't got any bike boots you don't need, do you?"

"Crazy is a very misunderstood term, it's a fine line that some of us can lean over and still keep our balance" (thanks RB550Four)

Offline Terry in Australia

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I also have the largest selection of used CB750 clutch plates in the southern hemisphere.......... ;D

😎😎😎

Here you go mate, have you ever seen more CB750 clutch plates in one place? ;D

Swamp Rat Saturday 18 May 2019 Drag pipes Terry's used clutch plates by Terry Prendergast, on Flickr
I was feeling sorry for myself because I couldn't afford new bike boots, until I met a man with no legs.

So I said, "Hey mate, you haven't got any bike boots you don't need, do you?"

"Crazy is a very misunderstood term, it's a fine line that some of us can lean over and still keep our balance" (thanks RB550Four)

Offline MoMo

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^^^^The disease keeps spreading ::)

Offline Terry in Australia

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Anyway, another day, another day older. Election day today, when the folks get to decide who screws us for the next several years. I was reminded by the wife that I need to fix two leaking toilets that have been dripping for the last few weeks, or she threatened to call a plumber! Calling a plumber would severely hamper my parts buying, so I said "Yes Dear" and drove over to the local hardware store via the Caltex gas station to fill my work car, then the nut and bolt shop to buy some exhaust flange screws, then the hardware store, and finally stopped in at the local school to vote on my way home.

My cousin Rod is a really good mechanic, not just really good, he's gifted. He's one of these guys who can just listen to an engine running, and tune it by ear, no fancy vacuum gauges or timing lights, dwell meters etc, required. He rudely called me a "sh1thouse Mechanic" when I was 13 or 14, so it seemed appropriate today that my first mechanical task was repairing two leaking toilets. Thank God we don't have three.....

Anyhoo, I was thinking about the ol' Swamp Rat. When I should have been tearing the engine out to prepare the frame for paint etc, I had the little bag of screws to attach some cleaned up exhaust flanges on, so I thought, "Why not" and dragged out enough bits to put my old Drag Pipes on the old pile.

Swamp Rat Saturday 18 May 2019 Drag pipes 1 by Terry Prendergast, on Flickr

Swamp Rat Saturday 18 May 2019 Drag pipes by Terry Prendergast, on Flickr

I was trying to remember when I bought these pipes, it was either 1980 or 1981, when I was either 20 or 21. Wow, I'm gonna be 60 next year, how things have changed to just about everything but these old bikes. By the time I bought these I was a CB750 veteran, having owned my first CB750 when I was 18. As nice as it was to own a shiny new CB750F, I loved my K1 a lot more, bought it for $200 as a non-runner, got it going, blew it up (thanks to a professional "mechanic" using silicone instead of buying new gaskets) rebuilt it, (myself this time) and kept it until I bought a Kawasaki 900 four or five years later. The drag pipes didn't stay on that long though, I bought a beautiful Walker exhaust a couple of years later that was a better system, but the old drag pipes are handy to throw on any old CB750 just to get it out on the road to test.

I installed new exhaust gaskets , and to hold them in, I glued them to the flanges with some silicone exhaust sealant to hold them in place which worked very well. The new screws were great, the nut and bolt shop had new 8 x 1.25mm countersunk screws in shiny zinc with phillips heads, just like the $3 per screw Honda items, for 50 cents each. I bought enough for the next project, assuming that there will be another CB750 project after this one. I thought it might be handy to have a throttle attached, so I scrounged one up and found all the cables I need (throttles, tach and speedo) and installed the throttle.

I fired the sucker up (started first kick again) and took a vid.


Then I got all philosophical and talked to myself about drag pipes.


Anyway, it was a good day, working first on a couple of sh1thouses, then working on a POS. Don't get me wrong, I love these old POS', and am having a lot of enjoyment bringing it back to life. More tomorrow. ;D




   
« Last Edit: May 18, 2019, 04:09:20 AM by Terry in Australia »
I was feeling sorry for myself because I couldn't afford new bike boots, until I met a man with no legs.

So I said, "Hey mate, you haven't got any bike boots you don't need, do you?"

"Crazy is a very misunderstood term, it's a fine line that some of us can lean over and still keep our balance" (thanks RB550Four)

Offline Terry in Australia

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OK, so while I'm thinking about what next to do to the Swamp Rat (which includes not painting it, just bolting everything onto it to make it a true "Rat" right now) I turned to my poor Yamaha FJR1300. The FJR is a magnificent beast, if you could imagine a Goldwing that is not so fat, but way more powerful, that goes around corners like a sports bike, and stops on a dime. The cops here ride them in several states as they are fast (170 MPH top speed) and the one cop I spoke to who was riding one when he pulled me over in Canberra for a random breathalyzer test told me that the cops love them.

Terry's FJR1300 2016 Canberra by Terry Prendergast, on Flickr

I just watched a youtube vid of a guy who rode his FJR1300 1288 miles in 21 hours, only stopping for fuel and a walk around, and I thought to myself, "I've gotta do that one day soon". I've got a mate in Cairns (Far Northern Queensland) who's not real well at the moment whose invited me up to visit him before we both get too much older and I'm thinking a ride up there would be a nice way to spend a little time. It's just shy of 2000 miles to his place, so if I do the ride, I think my FJR will get the nod, either that, or my Triumph Rocket III, they're both great mile munchers.

Mine is an interesting example, it's a very early 2001 build "Gen 1" FJR that I bought from the second owner in 2016. Finding one as old as mine is pretty rare as they didn't sell anywhere in big numbers until around 2003, certainly in this part of the world. The guy I bought it from was a teacher at a Christian School in Nhill, in Western Victoria, who rode the 100 mile round trip from his home in Horsham every day, 5 days per week, and to Sunday School every Sunday, so averaged 600 miles (1000Km) per week. He'd advertised it with a start price of $1500 (extremely cheap for such a bike) but the mileage (227,000 Km or 142000 miles) frightened off any bidders, so by about day 3 or 4, with no bidders (but lots of watchers) I contacted him and offered him $2000 (about $1500 USD) and he accepted. The wife and I drove the 400 mile round trip, I gave him the dough, he handed over the keys, the owners manual and toolkit, some genuine Yamaha spares, helped me load it, and he and his wife made us lunch. What a nice guy!

Anyway, I rode it every day to work in Canberra, did 2 trips to Melbourne and back the long way (1000 mile weekends)and due to a brain fart, forgot to renew the registration until 4 months after it expired, so it's been parked in various garages ever since then, without firing a shot. Recently my son Tim bought a new Royal Enfield 650 Continental GT, and I needed some garage space for it, so decided to move the big Yam back to the self storage unit where I keep 3 other bikes.

Tim's Royal Enfield Conti GT 26 Apr 2019 3 by Terry Prendergast, on Flickr

I fired it up (it's been on a battery tender for 3 years) and it started instantly, but was idling really high (4000 RPM) so thinking that something may have been stuck, I jumped on and rode it around the block. I'd just pulled back into my carport when it let out a "BANG", and steam and muddy coolant flew in all directions! Oops!

Terry's FJR1300 Explosion 26 Apr 2019 4 by Terry Prendergast, on Flickr

Bloody hell! Had I blown the water pump off? Was the engine fcuked? It was still running (@4000 RPM) and sounded OK, but I switched it off, and as the sun was slowly setting, parked it in my driveway under a bike cover until I had time to look at it. Yesterday was a magnificent Autumn (Fall) day, so as I was at a crossroads with which was I was gonna go with the Swamp Rat, I took a peek at the FJR. As is the case with modern bikes they're swathed in plastic, so I was surprised that it only took around 20 minutes to remove all of the lower fairing sections so I could locate the source of the coolant explosion. As it was, it was pretty easy to spot.

Terry's FJR1300 coolant system fix 17 May 2019 by Terry Prendergast, on Flickr

Yep, the ol' bottom radiator hose was toast.

Terry's FJR1300 coolant system fix 17 May 2019.jpg 1 by Terry Prendergast, on Flickr

After removing a few more parts, including the radiator, I was able to get the hose and another one in almost the same condition, and replace them with some "lightly" used, but near perfect sections I cut from a lot of Gen 2 FJR1300 hoses I bought for 40 bucks on Ebay. Not Ideal, but the OEM new hoses were well over $100 each, so I saved a few bucks as well.

Terry's FJR1300 coolant system fix 17 May 2019.jpg 2 by Terry Prendergast, on Flickr

While I was at it, I located a good used thermatic fan off a low mileage crashed bike that I bought back in 2016 when I thought mine was not working, as the ol' FJR got a bit hot one night in city "Bumper to Bumper" traffic. As it turned out, the original was seized. Well, it has done 147000 miles now, so I suppose I can't really complain, I think I paid less than 100 bucks for the replacement fan, which works great.

Terry's FJR1300 coolant system fix 17 May 2019.jpg 4 by Terry Prendergast, on Flickr

Okay, so I put everything back on (less the fairing panels) filled it with coolant, fired it up, and it did the 4000 RPM idle thing again, and almost immediately boiled it's guts out! Bugger! I switched it off, and let it cool down, and noticed that  while the engine was hot, the radiator wasn't. Hmmnn, that brought back memories of farting around with old Subaru's in 2015, and it turned out that there was an airlock around the thermostat, not allowing the thermostat to open, causing the coolant in the block to overheat, while the coolant in the rad was barely luke warm. Could the thermostat be buggared? Looking at what came out when it went bang, quite possibly. Either way, the thermostat needed to be looked at.

Terry's FJR1300 coolant system fix 17 May 2019.jpg 9 by Terry Prendergast, on Flickr 

As it was getting late and i'd been crawling around my driveway for about 5 hours, I decided to give it a miss and get drunk instead. (easy to do nowadays, one "Ginger Joe" alcoholic Ginger Beer and I'm anybody's) Today I paid to download a genuine factory workshop manual, mainly to see where the hell the thermostat is located, because they changed the location on the two later "Generations". It looked like the thermostat was up under the fuel tank, so tonight when I got home I pulled the tank back as far as I could, but as it turned out, didn't dig as deep as I needed to under the huge pile of hoses, pipes and cables that you find on a modern bike.

's FJR1300 coolant system fix 18 May 2019 by Terry Prendergast, on Flickr

I drained the tank as best as I'm able, and tomorrow I'll remove it completely, because it'll be easier to get to the thermostat with the tank completely removed and of course, being a modern bike, there is no fuel tap. Anyway, I was running out of light, so I covered it up again, and retreated inside. More tomorrow. ;D
I was feeling sorry for myself because I couldn't afford new bike boots, until I met a man with no legs.

So I said, "Hey mate, you haven't got any bike boots you don't need, do you?"

"Crazy is a very misunderstood term, it's a fine line that some of us can lean over and still keep our balance" (thanks RB550Four)

Offline Korven

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The hose that got shredded (rip) was it before or after the thermostat? Might have been alot of pressure in that hose if the water was boiling. Nice to get all that sorted out.

Offline PeWe

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2000 mile trip without sleeping while driving on very boring roads with minimum of curves?
Good roads OK with 1000km each day. I have driven my bike without sleeping from Austria to home, around 1800km. Done it twice in the 80's, no more! ;)
I had to twist throttle to 150-170 km/h the last 400 km to not fall asleep nighttime...
Autobahn in Germany was good back then.
CB750 K6-76  970cc (Earlier 1005cc JMR Billet block on the shelf waiting for a comeback)
CB750 K2-75 Parts assembled to a stock K2

Updates of the CB750 K6 -1976
http://forums.sohc4.net/index.php/topic,180468.msg2092136.html#msg2092136
The billet block build thread
http://forums.sohc4.net/index.php/topic,49438.msg1863571.html#msg1863571
CB750 K2 -1975  build thread
http://forums.sohc4.net/index.php/topic,168243.msg1948381.html#msg1948381
K2 engine build thread. For a complete CB750 -75
http://forums.sohc4.net/index.php/topic,180088.msg2088008.html#msg2088008
Carb jetting, a long story Mikuni TMR32
http://forums.sohc4.net/index.php/topic,179479.msg2104967.html#msg2104967

Offline SOHC4 Cafe Racer Fan

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Roadracer Josh Hayes raced a FJ1200 and won at the Phillip Island Classic this year.  The frame was built by Dennis Curtis (CMR Racing in Canada). 

Bad/good ideas . . .
1975 CB550K1 "Blue" Stockish Restomod (http://forums.sohc4.net/index.php?topic=135005.0)
1975 CB550F1 frame/CB650 engine hybrid "The Hot Mess" (http://forums.sohc4.net/index.php/topic,150220.0.html)
2008 Triumph Thruxton (http://forums.sohc4.net/index.php/topic,190956.0.html)
2014 MV Agusta Brutale Dragster 800
2015 Yamaha FZ-09 (http://forums.sohc4.net/index.php/topic,186861.0.html)

"There are some things nobody needs in this world, and a bright-red, hunch-back, warp-speed 900cc cafe racer is one of them — but I want one anyway, and on some days I actually believe I need one.... Being shot out of a cannon will always be better than being squeezed out of a tube. That is why God made fast motorcycles, Bubba." Hunter S. Thompson, Song of the Sausage Creature, Cycle World, March 1995.  (http://www.latexnet.org/~csmith/sausage.html and https://magazine.cycleworld.com/article/1995/3/1/song-of-the-sausage-creature)

Sold/Emeritus
1973 CB750K2 "Bionic Mongrel" (http://forums.sohc4.net/index.php?topic=132734.0) - Sold
1977 CB750K7 "Nine Lives" Restomod (http://forums.sohc4.net/index.php?topic=50490.0) - Sold
2005 RVT1000RR RC51-SP2 "El Diablo" - Sold
2016+ Triumph Thruxton 1200 R (http://forums.sohc4.net/index.php/topic,170198.0.html) - Sold

Offline 754

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Likely one of these , they were getting shipped to a team that would race them at Phillips.
 3 were getting sent out .
Maker of the WELDLESS 750 Frame Kit
dodogas99@gmail.com
Kelowna B.C.       Canada

My next bike will be a ..ANFOB.....

It's All part of the ADVENTURE...

73 836cc.. Green, had it for 3 decades!!
Lost quite a few CB 750's along the way

Offline Terry in Australia

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Yep, the old FJ1200 was a nice bike, I owned one for a few years before the FJR1300. I donated it to charity along with my big black Goldwing in 2016. The FJR1300 is an entirely different design, the only thing the two have in common is "FJ" as the start of their model nomenclature. While I loved my FJ1200, the FJR1300 is a much nicer, much faster bike, with the added complexity of water cooling and electronic fuel injection.

Terry's FJ1200 by Terry Prendergast, on Flickr

I dont think I'd try to ride the huge distance to my friends place in a couple of days Per, I'm too old and broken to attempt that, but an easy 600-700 mile day would be a snap on the big beast, and as opposed to Europe, the further north you ride in Oz, the more interesting the scenery. ;D


« Last Edit: May 21, 2019, 01:29:32 AM by Terry in Australia »
I was feeling sorry for myself because I couldn't afford new bike boots, until I met a man with no legs.

So I said, "Hey mate, you haven't got any bike boots you don't need, do you?"

"Crazy is a very misunderstood term, it's a fine line that some of us can lean over and still keep our balance" (thanks RB550Four)

Offline SOHC4 Cafe Racer Fan

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Likely one of these , they were getting shipped to a team that would race them at Phillips.
 3 were getting sent out .

Yes, indeed.
1975 CB550K1 "Blue" Stockish Restomod (http://forums.sohc4.net/index.php?topic=135005.0)
1975 CB550F1 frame/CB650 engine hybrid "The Hot Mess" (http://forums.sohc4.net/index.php/topic,150220.0.html)
2008 Triumph Thruxton (http://forums.sohc4.net/index.php/topic,190956.0.html)
2014 MV Agusta Brutale Dragster 800
2015 Yamaha FZ-09 (http://forums.sohc4.net/index.php/topic,186861.0.html)

"There are some things nobody needs in this world, and a bright-red, hunch-back, warp-speed 900cc cafe racer is one of them — but I want one anyway, and on some days I actually believe I need one.... Being shot out of a cannon will always be better than being squeezed out of a tube. That is why God made fast motorcycles, Bubba." Hunter S. Thompson, Song of the Sausage Creature, Cycle World, March 1995.  (http://www.latexnet.org/~csmith/sausage.html and https://magazine.cycleworld.com/article/1995/3/1/song-of-the-sausage-creature)

Sold/Emeritus
1973 CB750K2 "Bionic Mongrel" (http://forums.sohc4.net/index.php?topic=132734.0) - Sold
1977 CB750K7 "Nine Lives" Restomod (http://forums.sohc4.net/index.php?topic=50490.0) - Sold
2005 RVT1000RR RC51-SP2 "El Diablo" - Sold
2016+ Triumph Thruxton 1200 R (http://forums.sohc4.net/index.php/topic,170198.0.html) - Sold

Offline spotty

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  • cb750....for when a Vmax is just too much bike
    • spottys world of vmaxes and great danes

I dont think I'd try to ride the huge distance to my friends place in a couple of days Per, I'm too old and broken to attempt that, but an easy 600-700 mile day would be a snap on the big beast, and as opposed to Europe, the further north you ride in Oz, the more interesting the scenery. ;D

and the further north you ride the redder the necks get too
i blame Terry

Offline 754

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 Terry what you just did to the FJ, is something I am just not willing to do on a motorcycle..
 Maybe partly laziness, but just not what I want to work on .
 Great bikes though  very capable.,
Maker of the WELDLESS 750 Frame Kit
dodogas99@gmail.com
Kelowna B.C.       Canada

My next bike will be a ..ANFOB.....

It's All part of the ADVENTURE...

73 836cc.. Green, had it for 3 decades!!
Lost quite a few CB 750's along the way

Offline Terry in Australia

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Thanks Frank, I'm only doing it out of desperation mate, if I didn't want to ride it again I would have sold it as a project, but I just can't let it go, I think it's probably an anxiety thing, but once I start something it consumes me until its finished. That's why I could never do it for a living. ;D
I was feeling sorry for myself because I couldn't afford new bike boots, until I met a man with no legs.

So I said, "Hey mate, you haven't got any bike boots you don't need, do you?"

"Crazy is a very misunderstood term, it's a fine line that some of us can lean over and still keep our balance" (thanks RB550Four)

Offline PeWe

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OK, Terry, shorter distances per day will make that to a fun journey.
You'll plan how to do it and know what to see along the road? Like Henry Cole on World's Greatest Motorcycle Rides on Travel Channel.

You might find more projects  during that trip!
CB750 K6-76  970cc (Earlier 1005cc JMR Billet block on the shelf waiting for a comeback)
CB750 K2-75 Parts assembled to a stock K2

Updates of the CB750 K6 -1976
http://forums.sohc4.net/index.php/topic,180468.msg2092136.html#msg2092136
The billet block build thread
http://forums.sohc4.net/index.php/topic,49438.msg1863571.html#msg1863571
CB750 K2 -1975  build thread
http://forums.sohc4.net/index.php/topic,168243.msg1948381.html#msg1948381
K2 engine build thread. For a complete CB750 -75
http://forums.sohc4.net/index.php/topic,180088.msg2088008.html#msg2088008
Carb jetting, a long story Mikuni TMR32
http://forums.sohc4.net/index.php/topic,179479.msg2104967.html#msg2104967

Offline Terry in Australia

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Ha ha, well there might be some projects coming my way when I get there Per, Davey (who still has his K2 that he bought new in 1972) told me that he's moving closer to the beach and will be downsizing his bike collection. He still owns pretty much every bike he ever bought, and still has the K0(? might be a K1, I don't remember) that I gave him in 1981, along with lots of Kawasaki two stroke twins and triples, an ex-Milwaukee Police  Harley Electra Glide he bought back in 1985, a BSA Bantam, and some other stuff I've forgotten. He said something about giving them to his brother Pete, and me, so who knows? I wouldn't mind getting my old CB750 back, and maybe a Kawasaki 2 stroke?

Anyway, enough project dreaming. So I got home from work, and went straight out to the driveway to do some more work on the ol' FJR. I took the tank off (after removing four hoses and several electrical connectors...........) and took a look under the front.

FJR1300 Tuesday Thermostat tweaking 21 May 2019 by Terry Prendergast, on Flickr

Hmmnn, that thing isn't the thermostat housing, that's the air pump thingy that blows air into the cam cover via some reed valves. It's some EPA thing and you can buy a set of block off plates, or just cap the pipes in and out.

Deeper, much deeper, i found the thermostat housing. How the fcuk am I gonna get that out?

FJR1300 Tuesday Thermostat tweaking 21 May 2019 1 by Terry Prendergast, on Flickr

But after much head scratching and removing frame braces, disconnecting more hoses, pipes, electrical connectors and rad hoses, I finally got it out, and opened it up.

FJR1300 Tuesday Thermostat tweaking 21 May 2019 4 by Terry Prendergast, on Flickr

While filthy, there wasn't a lot of mud in there really, so I dropped the thermostat into the old shed kettle, boiled it, and it opened fine. Well that didn't really explain why it's boiling, but was good to know that I didn't need to buy a new one. I also got the garden hose out and sprayed water into the engine block's water jacket via the top two ports and watched it coming out the drain hole in the water pump, then sprayed water into the top hose to back flush the cooling system, and once again, no obvious blockages.

I'm still clutching to the "air lock" theory, so I drilled some extra holes around the circumference of the thermostat as I was advised to do with the old Subaru's, and yes, I drilled an extra hole in my finger while I was at it.

FJR1300 Tuesday Thermostat tweaking 21 May 2019 6 by Terry Prendergast, on Flickr

By this stage it was getting dark out, and my wife called me inside. No worries, I was tired, needed a drink and something to stop the bleeding, so I put a bike cover over the big blue beast, and called it a night. More tomorrow. ;D     
I was feeling sorry for myself because I couldn't afford new bike boots, until I met a man with no legs.

So I said, "Hey mate, you haven't got any bike boots you don't need, do you?"

"Crazy is a very misunderstood term, it's a fine line that some of us can lean over and still keep our balance" (thanks RB550Four)

Offline Terry in Australia

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Well another nice Autumn (Fall) day here, so after I got home from work I went straight outside to start putting the ol' FJR back together. Surprisingly it all went very well, and within a couple of hours I had everything back together, re-gassed the tank, and filled up the radiator. I'd bought some radiator flush yesterday, so I dumped it in the rad, with a gallon or so of slightly dirty coolant that I'd collected when I drained fresh coolant from the bike on Sunday after I'd replaced the blown hose, and it had boiled again.

FJR1300 wednesday Thermostat tweaking 22 May 2019 by Terry Prendergast, on Flickr

All was looking good, until I noticed a thin stream of coolant dribbling onto the concrete, apparently from the thermostat, which was tucked up away under the frame where I'd been working yesterday? Buggar! Okay, soo I undid the tank bolts and flipped it back, pulled out the frame cross member, and checked the thermostat housing, and sure enough, there was some coolant around the housing! Damn! On closer inspection though, it turned out I hadn't tightened the clamp on the top radiator hose at the thermostat housing! I quickly nipped it up, replaced the cross member, put the tank back in place, and fired it up.

It still revved too high (started at around 1500-1800 RPM, then quickly accelerated to almost 4000 RPM! Buggar again! By this stage the coolant in my special "Burping funnel" (very handy for Subaru boxer engines) was hot, and rising towards the top, so I shut it down again. I've left it overnight as is, hoping that it'll burp it's way down overnight. I did some internet research and there was some discussion of an identical issue with another Gen 1 FJR 1300, talking about an air lock in the coolant hoses that run to the injector rail. That's quite possible, if the coolant was low while it was sitting for 3 years, it could well be that my starting it after so long has pumped coolant back up the injector rail, and caused an air lock. I'll check it out tomorrow night.

To add to my cuts, scratches and drill hole in my finger, I managed to pinch my thumb with some pliers, so I've now got a nice blood blister to add to my injuries. I think I need to slow down.............. ;D

FJR1300 wednesday Thermostat tweaking 22 May 2019 .jpg 1 by Terry Prendergast, on Flickr   
I was feeling sorry for myself because I couldn't afford new bike boots, until I met a man with no legs.

So I said, "Hey mate, you haven't got any bike boots you don't need, do you?"

"Crazy is a very misunderstood term, it's a fine line that some of us can lean over and still keep our balance" (thanks RB550Four)

Offline Gurp

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Terry looks like me everytime i get a few tools in my hands.
slow Progress 74 cb550.

Poor boy chop 73 CB500 chop

Future project 77 Cb750 Amen Savior

Online jgger

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Terry I hear you on the hand/finger wounds. When my girls were little I would come home from work and one or both would get on my lap and show me a boo boo they got that day. This would turn into a game we used to call "count the boo boo's on Daddy's hands. " Being a carpenter there was never any shortage of them. Once we hit 7-10 then theirs didn't seem to bother them any more. I think the record was around 17!

Now on the other hand (so to speak) , if you are looking for sympathy ...........it's in the dictionary between syphilis and suicide.  At least that what my Dad used to tell me, I looked it up..........he lied.
« Last Edit: May 22, 2019, 09:34:48 AM by jgger »
"The SOHC4 uses a computer located about 2-3 ft above the seat.  Those sometimes need additional programming." -stolen from  Two Tired

The difference between an ass kisser and brown noser is merely depth perception.  Stolen from RAFster122s

Offline 754

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Take the drill it will fix the blister.
Maker of the WELDLESS 750 Frame Kit
dodogas99@gmail.com
Kelowna B.C.       Canada

My next bike will be a ..ANFOB.....

It's All part of the ADVENTURE...

73 836cc.. Green, had it for 3 decades!!
Lost quite a few CB 750's along the way

Offline PeWe

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You are very energetic with your builds and bikes, Terry!
The very beautiful Yamaha long distance cruiser is a must to have as a good runner :) A CB750 is good therapy, as Lego or Mechano for adults/very old boys  8)
« Last Edit: May 22, 2019, 10:56:13 AM by PeWe »
CB750 K6-76  970cc (Earlier 1005cc JMR Billet block on the shelf waiting for a comeback)
CB750 K2-75 Parts assembled to a stock K2

Updates of the CB750 K6 -1976
http://forums.sohc4.net/index.php/topic,180468.msg2092136.html#msg2092136
The billet block build thread
http://forums.sohc4.net/index.php/topic,49438.msg1863571.html#msg1863571
CB750 K2 -1975  build thread
http://forums.sohc4.net/index.php/topic,168243.msg1948381.html#msg1948381
K2 engine build thread. For a complete CB750 -75
http://forums.sohc4.net/index.php/topic,180088.msg2088008.html#msg2088008
Carb jetting, a long story Mikuni TMR32
http://forums.sohc4.net/index.php/topic,179479.msg2104967.html#msg2104967

Offline Terry in Australia

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Ha ha, thanks guys, I think I've done more bike stuff this year than I did all last year, so the old saying "The greatest wealth is health" is so true! And Jgger, your dad was probably putting a "G" rating on that quote, when I was in Special Forces my SSM (Squadron Sergeant Major) would work us very hard indeed, and his favourite saying was "If you're looking for sympathy, its in the dictionary between "Sh1t" and "Syphilis". I did check, and like everything else he said, he was right.

The weather turns to sh1t tomorrow, so I hope I get this bike sorted tonight, or I'll be twiddling my thumbs for a couple of days as both projects are out in the driveway and theres no room to work in my garage, in which case I might have to revisit my ZZR1100 build, I havent looked at it since before I went into hospital in August last year. It never ends! (Hopefully) ;D
I was feeling sorry for myself because I couldn't afford new bike boots, until I met a man with no legs.

So I said, "Hey mate, you haven't got any bike boots you don't need, do you?"

"Crazy is a very misunderstood term, it's a fine line that some of us can lean over and still keep our balance" (thanks RB550Four)

Offline Terry in Australia

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Well fcuk me, I think I fixed it! OK, so last night I was still scratching my head as to why it was revving at 4000 RPM and boiling it's guts out. To quickly summarise, I've replaced the blown bottom rad hose (and another one that looked pretty brittle) filled up the cooling system, but it was boiling the water in the block, while the rad was still cool, so I pulled the thermostat apart and checked to make sure it still worked, and then punched some holes around the circumference in case there was an air lock causing the boiling, as per the subaru issues.

The problem persisted tonight when I got home from work, so I thought I might take a peek at the water pump, just to make sure it was still rotating, and that it still had an impeller that worked. Surprisingly it was perfect inside, there was a bit of scale and corrosion here and there, but it was great. I even fired it up with the cover off to make sure the impeller was turning, and it was working fine. I reassembled it, fired it up, and it started revving it's guts out again, and then I noticed what looked like an idle adjustment screw, so I wound it down as far as I could, but it was still idling at around 2500 RPM, and started boiling again. Poop.

I'd read something about a "wax motor" which is attached to the injector rail, and relies on hot coolant to melt the wax, releasing a plunger that drops the RPM to 1000 RPM idle, once the ECU decides that the engine is warm enough. It should never idle at 4K RPM though, the "Experts" suggested that there might be an airlock in the coolant tubes that run from the thermostat housing to the wax motor, to the rad. Well the engine was running, so I popped off the little hose from the wax motor to the radiator, and instead of nice clean green coolant running out, a plug of mud shot out, followed by some more brown goop, followed by nice clean coolant, so I plugged it back into the rad.

I switched it off, let it cool down a tad, then fired it back up. It was idling (roughly) at around 200 RPM! That was my big "Aha!" moment. I wound the idle back up to 1000 RPM, and it happily idled at 1K RPM, until I decided that I'd done enough for one day, and packed up. Tomorrow (if it's not raining) I'll put all the plastics back on, and call it good. I'm kicking myself at the moment though, I've had a set of new spark plugs and a genuine Yamaha air filter to install in this thing for the last 3 years, and now I can pop the tank up without removing all the plastic filler panels, I can't remember where I put them? Oh well, hopefully I'll remember tonight or tomorrow and get that done, I know that the PO told me that he hadn't done a plug change in around 50,000 miles, and they're not iridiums, so they must be just about buggared. Lets hope I can find them! More tomorrow. ;D



   
I was feeling sorry for myself because I couldn't afford new bike boots, until I met a man with no legs.

So I said, "Hey mate, you haven't got any bike boots you don't need, do you?"

"Crazy is a very misunderstood term, it's a fine line that some of us can lean over and still keep our balance" (thanks RB550Four)