Topic: seanbarney41's 1975 CB750F!

[seanbarney41]

Did I now have a fully functional motorcycle? It took about 25 minutes including 2 full throttle plug chops to dial in the carbs for the Kerker and Henry Abe breadbox.  All it took was 135 mains and left everything else where it was at.  I still don't really know because I have not even had these carbs off the bike yet.  I did check float levels via clear tube and later, did a vacuum sync.  So the engine ran exceptionally smooth through the rev range.  I think the breadbox is killing a little high rpm fun but I have another idea on how to fix that.
   Brakes worked awesome...but the handling?...  Total crap head shaking and bouncing and bumping #$%*iness...What gives?  I had rebuilt the front forks, new steering head bearings, swingarm was inspected and found to be exceptionally tight and smooth.  I serviced the chain.  Maybe helped a little.  I went back through aligning the forks in the trees.  Maybe helped a little.  The tires were old and worn but not that bad?  I started looking at the wheels.  Lots of loose spokes on the front.  Tightened 'em and they quickly loosened and made no difference when they were tight.  Then I found these...
This is the amount of balance weight found on one wheel.
KIMG0009 by Sean Barney, on Flickr
ripped all that #$%* off and there was maybe some more slight improvement.  IMO these wheels were shot.  This is why I am totally not a fan of the stock steel rims with spokes.  Even perfect ones just suck imo.
Here is what I had and decided to use.
KIMG0101 by Sean Barney, on Flickr
These are from a special edition GL1000, so the front bolts on.  The rear laces right up to the f hub as it is dimensionally identical to a gl hub.  I sourced a spare f hub from member Kickstart, so I could polish ahead of time and copy the spoke pattern. 
There's that paint stripper again.
KIMG0019 by Sean Barney, on Flickr
KIMG0020 by Sean Barney, on Flickr
once again and throughout...gefwif
KIMG0021 by Sean Barney, on Flickr
KIMG0023 by Sean Barney, on Flickr
KIMG0024 by Sean Barney, on Flickr
Unfortunately, the only picture I have of the lacing and trueing process is this, spokes all sorted and counted...
KIMG0153 by Sean Barney, on Flickr
This was my first attempt at lacing and trueing.  It went well and was easier than I expected.  My usually totally useless and lazy shopmate Chris did actually put down the cell phone for 15 minutes and use some of his MMI training to perfect my merely acceptable trueing.  The icing on the cake, came when I got the wheel back from getting a new tire and NO balance weights were needed.  These wheels are lighter, strong, and quite round.  The only drawback is the rear 17".  I have not found a good tire size.  I used Pirelli Sport Demon in 130/90/17, to help make up the lost diameter.  Paired with a proportional 100/90/19 on the front, the handling is vague and tubby.  They do stick like glue though if you can get the thing heaved over.  At the least, the bike is safe, stable, and rides solid and smooth.

[seanbarney41]

This bike was now riding like a million bucks.  So installed a few more goodies sourced right here from members of the best motorcycle forum there is.  Clean original seat and sidecovers...
KIMG0100 by Sean Barney, on Flickr

[seanbarney41]

Anyway, has been a hoot sharing this bike with y'all.  Lord knows, you should stop by and take a spin 'cause yall deserve it.  Almost everything was sourced from this forum, knowledge included.  I have not even used everything I got and this bike is by no means done.
Thanks
KIMG0114 by Sean Barney, on Flickr
KIMG0086 by Sean Barney, on Flickr
KIMG0073 by Sean Barney, on Flickr
KIMG0059 by Sean Barney, on Flickr
KIMG0054 by Sean Barney, on Flickr

[slikwilli420]

Looks killer Sean. The gold rims really set it off.

[SOHC4 Cafe Racer Fan]

That's a beauty!

[seanbarney41]

Thanks very much guys

[gschuld]

Looks great Sean......

George

[seanbarney41]

Thank you George.  I really appreciate the compliments.

[seanbarney41]

I would also love the chance to learn from any and all critiques!

[Terry in Australia]

Looks good Sean, you were lucky to get a nice sound bike to start with, and I love your Rednecking attitude, like me you know that beauty is way more than just skin deep, and a bit of patina is something that should be admired, not covered up with a can of VHT. They're only original once. Good job.

Dang!  This bike must be good to get Terry to compliment an F!

Ha ha, credit where credit's due mate, you've done good work. Not sure about your front forks/brakes comments though, here's a pic of the Cafe Racer I built for Mike last year, it's got F forks with K3-6 calipers, with just a couple of small spacers for the K caliper and bracket on the right leg. Most of the post classic racers here use F forks, so they can install a fork brace like the one on this bike. With the Bandit 1200 MC and braided lines, it stops on a dime! Cheers, Terry.

Mike's Cafe by Terry Prendergast, on Flickr

[seanbarney41]

That's really interesting Terry.  I wonder what the heck was going on there?  While studying up for that brake swap, reading different old threads and such, I found lots of conflicting information about what exactly needed to be done to get that right caliper lined up.  I guess there just must be several possible different parts combinations.
     And thanks for the master cylinder idea.  I got it from your posts.  Although, there must be any number of Nissin masters from slews of different bikes from the same era that could be used just as effectively.
     And I do feel a fork brace is gonna be a good improvement here and plan on getting one.  I had initially planned on using one of those old tubular ones that bolt to the fender mounts, but decided it was just gonna make lining up the calipers even more difficult.

[Stev-o]

Well done Mate!   Enjoyed your style of write up on this...

[seanbarney41]

Really appreciate that, Steve-O...guess I just had nothing better to do on a crappy rainy Michigan in November saturday afternoon...this never ending rain is certainly NOT gefwif.

[Medyo Bastos]

Nice work, congrats!


Sent from my iPhone using Tapatalk

[seanbarney41]

Thank you very much sir.

[Terry in Australia]

That's really interesting Terry.  I wonder what the heck was going on there?  While studying up for that brake swap, reading different old threads and such, I found lots of conflicting information about what exactly needed to be done to get that right caliper lined up.  I guess there just must be several possible different parts combinations.
     And thanks for the master cylinder idea.  I got it from your posts.  Although, there must be any number of Nissin masters from slews of different bikes from the same era that could be used just as effectively.
     And I do feel a fork brace is gonna be a good improvement here and plan on getting one.  I had initially planned on using one of those old tubular ones that bolt to the fender mounts, but decided it was just gonna make lining up the calipers even more difficult.

No worries Sean, I liked the Bandit MC's because I was able to buy good used ones off low mileage bikes really cheap on Ebay when everybody wanted the GSXR ones with the schmancy remote reservoirs. They do work great though, first time out I performed an unintentional "stoppie! I've been looking for another pair of "F" lowers so I can install a fork brace, let me know if you see a pair going cheap? Cheers, Terry.  

[Bankerdanny]

The 550F has the wiring in the bucket like regular 550's. The wiring box seems to be in OK shape on my '76, but I haven't looked that hard. The headlight shell has a big crack in it. but I little fiberglass will fix that right up.

The replacement tail and trim I picked up (for the long horizontal trim piece, the tail piece on mine is actually in fine shape) is the Sunrise Flake Orange like your bike. My bike was badly repainted a blue similar to the Sapphire Blue on my 550, so I was originally thinking of repainting the bike the '75 orange like yours. But after sanding off the Bondo from the bottom of the tank I could see my bike was originally Sulfur Yellow and now I am leaning towards bringing it back to that.

Part of the outer plastic cover of my ignition switch is toast, but the switch my 550 is the same and I think that the broken piece on the 750 switch can be swapped for the good one from my old 550 switch.

I was looking at a '77 Wing a guy in Indiana was selling for $100 that we mostly toast, but had the wheels, brakes, and forks. But I hesitated and missed my window. I'm going to keep my eye on Craigslist over the winter and see what I can come up with. I wouldn't mind getting a wheel, fork, and brake setup from an F2/3 either. I really like the look of the Comstars.

[seanbarney41]

Hey Danny...
I swear I had a 550f parts bike that had that wiring pouch thingy but it was a hacked up mess so who knows.  I think I have a solid bucket, if you'd rather not fiberglass, but it really needs paint.

Even when those key switches work, I just assume they are living on borrowed time.  Every one I have had has failed...generally out in the boonies, in the dark.  So maybe have some jumpers with connectors ready to go in the tool kit.  It's really easy to just unplug the switch and plug in 2 or 3 jumpers to hotwire.

I'm not sure what I think about the sulfur yellow.  Ekpent has one in that color, and it does grab the attention.  Certainly, quite a novelty...and probably one of the easiest sohc4 colors to match.

Takes balls to rock some comstars.  So many hate 'em.  But they really are a superior wheel to the stock steel rims and wobbly spokes.  F2/3 forks are realistically, all things considered, a better swap than the GL forks, in my opinion.  Just now thinking Sulphur Yellow with comstars would be totally anti-social and cool!

I eagerly anticipate getting around to rebuilding my F3, as I have some really tasty parts collected up and set aside, but realistically, still a few years out...
DSCN0738 by Sean Barney, on Flickr

[Terry in Australia]

That F3 looks pretty good Sean, why not just ride it as is? I've got at least one all alloy comstar here that I rescued from a swap meet, same pattern as the F2/3, but way lighter, maybe from a CBX?

I was going to build a K bike with comstars front and rear, powered by an F2 engine many years ago, but got sidetracked. I've got a set of F2 forks, an F2 engine and some comstars, so I might have revisit my "K9" "Junkyard Dog" project..........

[seanbarney41]

Terry, I bought that bike about 5? or 6? years ago stuck from sitting and got it freed up and running.  It promptly ate its cam, rockers, and towers in the first 15 miles.  I cleaned out the plugged oil jet, threw a used f2 set in and rode the #$%* out of it for 12,000 miles.  I could go throw a battery in it right now and go pop some more wheelies...but it smokes more than one of Ekpent's Suzuki's and guzzles a quart of the slippery stuff in under 100 miles...them damn valve guides...

[Terry in Australia]

Yeah mate, my first F2 was a gem, I got it for a bargain from a bike shop because no-one wanted an F, it had been a trade in and they just wanted it out the door. The PO had really looked after it, and apart from an ignition problem when it rained (turned out to be the ignition switch) it was a really sweet runner.

My second one was an Ebay bargain, that had been crashed, been in a fire, and flogged to death. I restored it and put a K6 top end on it, and had that engine in and out several times. Eventually I replaced enough parts to make it go as nicely as it looked, but was disappointed that it sold for around half what it owed me. I kind of wish I kept it..........

[seanbarney41]

so fugly!  I love it!

[Bankerdanny]

I have never understood the hate for how Comstars look, particularly the style used on the F2/3.

[Stev-o]

I have never understood the hate for how Comstars look, particularly the style used on the F2/3.

They are not for everybody, Danny.  I just dont like mag wheels on a 70's bike, has to have spokes if it's mine.  I dont care for Lesters either, but I like the Enkei's on my '82 GPz550...

[ekpent]

 Yes nice write up Sean, that was a lot of typing   Give the Boyz a peek at your slabside Suzuki lingering in the shop. Get that one on the road and you will be waiting much longer at the stop signs for me to catch up when we ride together !!