Topic: 77 cb750k.. slowly coming along.

[garygnu]

So I bought a 77 cb750k a few weeks ago and this is my first time messing around with trying to modify a bike and I'm in a bit over my head I think.. right now I want to get the wheels and tires done.  I want to do 18's on the front and rear with these tires.. http://www.cokertire.com/popular-tire-applications/motorcycle/450-18-coker-classic-cycle-diamond-tread-blackwall-tire.html  I know that most of the time the rear wheel is much wider than the front, am I going to run into massive handling issues running the same tires on the front and rear?  Also I want to powder coat the rims, should I do it before or after they're assembled?  I've gotten mixed answers on that one.

I'm not going to lie, I'm a total noob when it comes to this, never tried to build or modify a bike in my life.  I'm really not looking to make some kind of show bike right now, I just want something that's going to be fun to ride around on.. We'll see what happens I guess.

Any input or suggestions are very much appreciated.

Shoot, no pictures until I figure out how to make my picture file size smaller.

[SOHC4 Cafe Racer Fan]

Going with 18" wheels front and back should not adversely affect handling. If you want to powdercoat the rims, you will need to do it before reassembling the wheel. PC bakes the finish onto the metal.  It's much easier to PC the rims and then lace the wheels, versus trying to mask the spokes and other parts.  If you wheel is truly fully assembled, you will also be baking the hubs including bearings (probably not a good idea because you will be cooking and degrading the grease). 

Since you will be sourcing a new front rim, you may simply want to buy pre-coated wheels, like the Sun wheels available through Buchanan's.

[70CB750]

Picture posting gets much better after 5 posts.

[onetruepunk87]

You'll also need to source a new rear rim as well, '77 has a 17" stock.

[garygnu]

Thanks for the replies.. I've got the rims coming today and the spokes coming friday.  I've got the hubs cut out of the wheels, bearings pulled,  and I'll be spending the weekend cleaning them up and getting everything ready to drop off for powder coating next Tuesday.  After seeing onetruepunk87's thread I'm getting totally stoked.

[garygnu]

Alright, so I've got the 2.15x18" rims in and the new spokes for the front and rear.. I want to go for this http://www.bikeexif.com/honda-cafe-racer-2kind of a look for the wheels and I'm having second thoughts about whether or not this setup with these tires http://www.cokertire.com/popular-tire-applications/motorcycle/450-18-coker-classic-cycle-diamond-tread-blackwall-tire.html is going to do the trick on my 750 vs. a 450?  Before I get everything powder coated and un-returnable does anybody have an opinion about this? 

You guys are awesome, thanks!

[garygnu]

So while I was at the bike shop today putting in an order for new sprockets and a chain I asked the guy about my next step, rebuilding my carbs.  He tried to look up some carb kits for me but couldn't find them.. he eventually said that they must not make carb kits for the 77-78k's because there were a lot fewer produced than the earlier models.  While this might be true, (I have no freaking clue about that), I've seen plenty of other people with 77's and 78's so there's gotta be a source for them.. anyone have a good spot for me to get my hands on some carb kit's and needles to re-jet?

[Bankerdanny]

They are out there, but he is correct that carb parts for the 77-78 750's are harder to find because of the limited number of bikes produced.

[SOHC4 Cafe Racer Fan]

Or you can just buy a set of CRs!

[Stev-o]

4.5" is pretty wide for a front tire, don't plan on using the fender, right?


Parts n More has the carb kits.....


http://www.partsnmore.com/parts/honda/cb750/?filters%5Bfitting%5D=custom&filters%5Bcategory%5D=carb

[garygnu]

Or you can just buy a set of CRs!

I'll admit that I don't know what CR's are.. after spending almost a G on my wheels alone, I'm trying not to buy that much more for the moment.. this is a poorman's build.  I really wanted that specific look for my wheels, and you have to pay to play.. but I'm tapped for the moment.

4.5" is pretty wide for a front tire, don't plan on using the fender, right?

Parts n More has the carb kits.....


http://www.partsnmore.com/parts/honda/cb750/?filters%5Bfitting%5D=custom&filters%5Bcategory%5D=carb

No, I'm not interested in using the stock fender but I thought that I could bob it, extend the bracket and use some bondo to come up with something cool.. IDK.  I don't necessarily want to go fenderless on the front but it might be tricky coming up with something that works with my setup.  Input is very much appreciated.  Thank you so much for the link on the carb kits.. I was contemplating having to buy 76 carbs and doing a bunch of weird crap.  Honestly I googled the #$%* out of 77 cb750k carb kits and didn't come up with that link.. they need to advertise better or something.  Or maybe I'm blind.  Idk.

They are out there, but he is correct that carb parts for the 77-78 750's are harder to find because of the limited number of bikes produced.

I jumped on this bike because it's my birth year but now I'm wondering if I shoud've just waited for a 76 and called it good.. c'est la vie or something I guess.

Thanks for the responses guys.. seriously, the only way this is going to get done correctly is with some help from the sohc guru's.   I'm going to open a photobucket account so I can start posting pictures.

[TikiTodd]

rebuilding carbs is not hard to do, the actual taking apart and putting back together, but if you've never done it before i'd highly recommend having the carbs professionally rebuilt.  It could save you a lot of headaches down the road.
Have fun wrenchin' n ridin'...


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[garygnu]

Well I've made some progress on my bike, but don't really have that much to show for it yet.. I'm still waiting on my wheels.  Still. waiting. on. my. wheels.  Aaaanyways let's recap.

Started with this:



It looks better in the pictures than it really was, lots of rust and little stuff just wrong or jerry-rigged.  But it started right up cold and seemed to run pretty good so I changed the oil and gas and rode it around like this for a week or so. (minus the dumb luggage rack)  Then I began the dismembering.



Took the carbs completely apart and cleaned and rebuilt them. I'm going with the Uni pods.. yes I'm saving my airbox.



I dropped my gas tank when I was draining the old gas out.. I haven't been that angry for a while.



But after sandblasting, a pretty decent bondo job, primer and paint I think it looks pretty cool.



I used my dremel to grind the side covers down so they don't have that square part that flows into the lines of the airbox.. I think it'll look cool.  I'm waiting on the plasti-fix kit to come in the mail so I can fix the crack and paint them.



The bane of my existence.. all parts powder coated ready to be laced up.



I ordered the rims from one place and the spokes from buchanans.. (first mistake)  got the bearings taken out, got everything powdered, took them to a shop to get em laced up, shop says the front wheel went together fine but the spokes for the rear are wrong and they cant do it plus the powder job was and scratching/flaking off way too easy, buchanans says the spokes are fine and offer to comp me the labor on lacing the rear if I ship it down, I ship it down, they say the spokes are fine but the rim isn't drilled correctly for a rear hub, I gave em the go ahead to drill em, they're currently working on it.. when I get that back I'll get both wheels powdered again (luckily comp'd by the shop that did it originally) get the tires mounted and balanced and have my bike on wheels again.

After I get the bike back on wheels I'm going to take the center stand off and put my new exhaust on.  It's a yoshi style from gpmotorworks.. it looks really fricking nice just sitting there on the box doesn't it?  Then carbs and I should be able to try to start it up again.



So here's where I'm at now.. new handlbars, grips, and levers.





I'm going with flat black until I decide on a color. 

The problem I'm currently tackling is trying to ground the new blinkers so they stay on as running lights.  The stock blinkers were dual filament but apparently they didn't need a ground wire because they're grounded in the housing.. any tips on where I can ground them out?

Thanks!

[fendersrule]

Those 77k side cover emblems are plentiful on eBay. Be lucky you don't have the '78 year.

The best thing to do was NOT to smoother the dent with bondo but instead to use a stud puller to do the job right...if you ever sell the bike, someone like me is going to find it (and fix it right).

Not trying to be a @$$hole, but you started with what appears to be a damned fine '77k in stock condition (minus the pipes). Now it's flat black (probably rattle canned). I agree that the stock '77-78 colors suck (black is merely "ok") but you may have been better to have left it alone until you decided on something and then have it professionally done. Now if you do it "right" it's going to be more work.

When you mess with the air intake on these bikes you better get ready for days of tuning and jet-changing. Those uni-filters are better than "pods" but that doesn't mean you are in the clear from a tuning perspective.

I hope that you get what you want from your build, but I guess I just hate seeing great condition stock bikes being "customized" into something else that will kill their value (77-78's don't have THAT much value anyhow...at least now). This isn't a bad thing, but it's completely opposite of what I do (I bend the rules myself a little bit within reason

Stock side covers also suck, quite a bit. If they arn't cracking now (One of them is), then they will crack. I recommend Franken's side covers. He's a forum member, and for around $70 (can't remember) you will get something that is almost unbreakable.

Personal opinion here too, but looks like you had a 4 into 2 exhaust. I personally hate the sound of them. You did make a wise choice going 4 into 1...but only because 4 into 4 are a PITA to find.

Good luck, just my perspective.

[garygnu]

Those 77k side cover emblems are plentiful on eBay. Be lucky you don't have the '78 year.

The best thing to do was NOT to smoother the dent with bondo but instead to use a stud puller to do the job right...if you ever sell the bike, someone like me is going to find it (and fix it right).

I don't know if you can see it in the picture but the dent had quite a bit of texture in it, I consulted my brother in law who does custom painting for cars and motorcycles and he recommended I bondo it the best I can for right now until I bring it to him to finish it.. and then he'll do a better job.  It's not like I just slathered it on there, It took me 6 layers and sanding to get it there, I'm not saying it's perfect but it's pretty damn close.  I'm not even sure if I'm even going to keep this tank on there.. the K tank is pretty wide.

Not trying to be a @$$hole, but you started with what appears to be a damned fine '77k in stock condition (minus the pipes). Now it's flat black (probably rattle canned). I agree that the stock '77-78 colors suck (black is merely "ok") but you may have been better to have left it alone until you decided on something and then have it professionally done. Now if you do it "right" it's going to be more work.

Again, it looked better in the pictures than it was.  I've come across this perspective from others since I started this project and the best answer to it I can come up with is that "Hey.. it's my bike, man."  I'm hopefully going to be riding this for many, many years to come and it will be an ongoing process.  I didn't want to start with a total basket case because I don't have the resources to do that and I'm not trying for nor am I a fan of the super cherry, chromed out, and sparkly things.. to each their own I say.  I'm going to ride this and so I'm the one that's going to have to be happy with it.

When you mess with the air intake on these bikes you better get ready for days of tuning and jet-changing. Those uni-filters are better than "pods" but that doesn't mean you are in the clear from a tuning perspective.

I have been warned about this, we'll just have to see how it goes.  I can always put the airbox back on if it comes to it but for now I want to try to use these filters.

I hope that you get what you want from your build, but I guess I just hate seeing great condition stock bikes being "customized" into something else that will kill their value (77-78's don't have THAT much value anyhow...at least now). This isn't a bad thing, but it's completely opposite of what I do (I bend the rules myself a little bit within reason

Stock side covers also suck, quite a bit. If they arn't cracking now (One of them is), then they will crack. I recommend Franken's side covers. He's a forum member, and for around $70 (can't remember) you will get something that is almost unbreakable.

Personal opinion here too, but looks like you had a 4 into 2 exhaust. I personally hate the sound of them. You did make a wise choice going 4 into 1...but only because 4 into 4 are a PITA to find.

Good luck, just my perspective.

Thanks for the response and I appreciate your perspective.. I figured I was going to get some flak for chopping up a nice stock bike but again, if you were able to look a little more closely you would see that there was quite a bit that just wasn't that great.  This is the first bike I've ever tried to work on at all and I'm really not looking to make some kind of a show bike quite yet.. I just want something that'll be fun to ride around on.

[garygnu]

So I'm having a problem getting a ground for the new blinkers up front and I'm pretty sure it's because the new ears I put on have these plastic spacers that are insulating them from the forks.  I was thinking about cutting some round bar and putting it in the gap in the spacers so that there's a contact between the ears and the fork tubes.  Hopefully then the nuts inside the bucket with the green wires that the blinkers screw in to will actually ground.





Any thoughts?

[garygnu]

I know it's been a while but here's where I'm at right now.  Still a lot of work left to go but it's starting and running ok.. still need to dink around with the jetting but I'm waiting for my Dyna electronic points to come in before I start that up again.



Obviously the seat needs to go.



I'm going with the DCC brat seat and it has these mounting bolts on the bottom like so..





Cutting the frame and welding on the hoop with the slugs is pretty straight forward... Any tips on how I can mount that seat nice and flush with the frame without having to totally rework everything in the battery box space?





Thanks in advance, you guys and this board have been a huge help in this project!

[flybox1]

Not trying to be a @$$hole, but you started with what appears to be a damned fine '77k in stock condition (minus the pipes). Now it's flat black (probably rattle canned). I agree that the stock '77-78 colors suck (black is merely "ok") but you may have been better to have left it alone until you decided on something and then have it professionally done. Now if you do it "right" it's going to be more work.

HAHA fenders, i kinda agree with you.  looked good from the start.  but we'll all be a PO someday 
Hey garygnu, when you get bored and want to sell it...i'll take it, i'm petty good at working on the flat black ones 
here's how mine started....

see you around the sound....

[calj737]

Gary - to fit the seat, you'll be best off "downsizing" your battery. Then you can relocate the battery tray to mount underneath the hoop, and even use a smaller tray altogether.

For your indicator ground wire issue; chase a wire back to the headstock and ground to the frame directly. Its just wire, run it where it needs to go.

Your bike is looking fine and coming along nicely. Don't let the purists derail your enthusiasm. Heck, you'll be giving a 35 year old bike a new lease on life!

I think your tank repair looks fine. It obviously wasn't dented badly, just road rash? Smoothing out with some bondo at this point is simple enough. And, when your B.i.L. does the paint work, he can wipe off the flat black with Acetone, then sand out the filler and scuff the original paint (or strip it to bare metal) before he paints it. Its not that much work. Besides, who knows when you'll get it painted, so fix it now (as you did) and ride on-

[garygnu]

Gary - to fit the seat, you'll be best off "downsizing" your battery. Then you can relocate the battery tray to mount underneath the hoop, and even use a smaller tray altogether.

For your indicator ground wire issue; chase a wire back to the headstock and ground to the frame directly. Its just wire, run it where it needs to go.

Your bike is looking fine and coming along nicely. Don't let the purists derail your enthusiasm. Heck, you'll be giving a 35 year old bike a new lease on life!

I think your tank repair looks fine. It obviously wasn't dented badly, just road rash? Smoothing out with some bondo at this point is simple enough. And, when your B.i.L. does the paint work, he can wipe off the flat black with Acetone, then sand out the filler and scuff the original paint (or strip it to bare metal) before he paints it. Its not that much work. Besides, who knows when you'll get it painted, so fix it now (as you did) and ride on-

Wow, my Dyna S points came in way sooner than I thought so it looks like I'm going to be dinking around with the jetting and whatnot before I finish the seat.  That actually works fine because I have to source a new battery at least and maybe a wire harness, Hondaman fuse plate, new reg/rec before I do the seat.  Any links for a good reliable low-profile battery? 

Also, thanks a lot for the help and encouragement.. I know the tank and side covers aren't spectacular, but until next winter when I disassemble everything to do the powder coating on the frame and maybe a fork swap it'll look a little mean and be fun to ride around on.  I've seen a lot of my bro's work and when I finally get inspired as to what I really want for a color scheme I know that it will be done as good as is humanly possible.  You know, I really don't even worry about thread#$%*ters implying I'm a tourist, because it is really cool, helpful, and worth it to hear from someone who can give some advice without needing to show off what a big ego they have about their own super "cherry" bikes.  Your bike is very #$%*ing cherry btw, awesome work.

Thanks man.

[calj737]

Oh, you misunderstand. I do have a huge ego too! I just didn't use it when responding 

As for a battery, I (and many others) use small Li-ion units. They are lighter weight, more expensive, vibration tolerant, and very small. I like Shorai batteries, and use the A2 frame size. If you do get a Li-ion battery, you should also use a high quality charger capable of managing the charge rate. I use the Shorai brand charger and am quite happy with both the battery, and the customer service. 100% replacement within 12 months. Cross shipped a battery to me (it wasn't actually bad in the end, but they sent me a new unit anyway).

You'll get dissenting opinions about batteries from many, and their input/advice is also good. Different experiences and budgets for different projects is my suspicion.

Grab a Rick's or Oregon Reg/Rec unit. They are the most popular aftermarket and never heard a bad word about either from anyone buying them.

Regarding a "fork swap", you can rebuild the stock forks with either progressive rate springs (fairly cheap) or upgrade them with cartridge emulators (a bit more expensive, but better). Both these methods retain stock tubes, and don't necessitate changes elsewhere in the triple tree, hubs etc... But, first of all, you should change your fork oil now. Treat is as probably neglected (unless I missed where you did service it) and drain the oil and re-fill with quality oil. It will help immediately.

And if/when you do pull your forks in the winter, also tend to the steering head bearings. Many upgrade to tapered bearings and discard the old races and balls. Smoother steering, less service, and better handling. These are all very low cost projects you can do yourself, with little experience or tools, by simply reading a few threads. And all these benefit your handling, steering and safety. Good expenditures!

The best part of what you're undertaking: it's been done before and there's tons of "how to's" available here. Lots of different methods used, so pick the one that suits your tools and skills and have at it. You'll be fine, your bike will look how you want it to, you'll love riding it, and you can take all the credit!

What could be better than that?

[garygnu]

Awesome advice..

I found the battery and reg/rec unit online but I'm going to have to wait until next week to order them I think.  That'll give me time to work on getting the Dyna ignition installed, jetting, carb sync, etc. out of the way tho so no biggie.

One of the first things I did when I disassembled everything was clean out the forks and replace the oil and seals, I probably should have done the bearings at that point but I was dealing with my wheels and just didn't. 

By swapping out the forks, I meant that I have this front end including the triple tree from an old Suzuki that I was thinking about using. 



I really like the dual disc's and I think it would look damn sexy with my wheels.. minus the fender of course. I'm pretty sure it's going to be big investment to do this and honestly I haven't even looked into whether or not that is feasible with this front end.  I got it practically for free tho so I took it and figured I'd worry about it when I'm not trying to just get on the road.

The fact that you're willing to take the time to help such an obvious noob with his build shows a lot of character.. thanks again man!

[calj737]

Are you after dual discs and spoked wheels? Or are you considering using the mags for front and rear?

If dual discs with spokes, all you need to do is buy another disc, caliper, mounting bracket, and deal with a slight mod on the tach gear. Done. The forks you show, don't offer a significant improvement in what you own, if properly rebuilt (or upgraded as previously mentioned).

If you want to swap a front end to dual discs with those mags, you may be in for a project... Possibly you'll also need to swap your triple trees, stem, etc, then deal with fitment issues on the back end.

Yup, dual discs are nice and do look really good. Member Godferrey can hook you up with all the pieces you need, plus thin and drill your current rotor. If adding dual discs, reducing the weight is advisable, drilling does improve wet braking. These are only single piston calipers.

Member here Pampadori (slingshot cycles) offers steel braided lines and hard lines to fit stock front ends. Great products, great service, and offers a 15% discount to SOHC members.

Many folks do swap a Suzuki front end, but it tends to be a GSXR with upside down forks. May not be the look you seek. Also, it does get pricey quickly.$350 for Cognito custom hub (bolt on configuration) new spokes $100, front end ($600 with rotors, pads, cli-ons and controls) plus bearings $40 and brake lines ($80). Do the math- Not for the faint of heart.

Call Godferrey! And upgrade to cartridges and SS lines. You'll save money, get really good braking performance, and you can bolt it all up in the garage in about 3 hours.

BTW - thanks for the earlier comment on my bike. Took it out tonight for some more shakedown rides. Gotta re-wire it with all new MotoGadget stuff this weekend... And the carbs need tuning. But otherwise, it really is a blast 

[SOHC4 Cafe Racer Fan]

Looks like that Suzuki front end is from a GS of one type or another, and that it has a Tarozzi style fork brace.  I'm not sure whether it is compatible with your 750 steering tube.  You can check out the All Balls Racing website that has lots of information on the compatibility of front ends. 

One of the easiest ways to go dual disc on a 750 is to swap in a 75-76 GL1000 front.  It is a direct plug and play -- nothing needed.  You just swap in the forks, brakes, discs, spacers, triple trees (from the GL) and bolt them in.  Done and done.

[garygnu]

I'm definitely after dual discs using the spoked wheels I already have.. I've seen that my right fork has the holes to set up (I guess) a super sport dual disc situation, but I didn't really connect it that all I had to do was source the disc, caliper, and I assume some sort of junction to combine the duals into one on the brake line. Derp.  That is probably going to be the best way to go.  I was thinking for a minute that I could drill my own rotors and get them thinned locally but it would probably be better to call Godferry and just ship it out to be done by a master.. brakes are sorta important I guess.  Perhaps I will wait on the cartridge emulators till the winter, from what I've seen after a quick internet search it can be kind of a deal.

CB750 Cafe Racer Fan, it's funny that you said that looks like a Tarozzi brace.. I thought that too but I couldn't see anything on it that said 'Tarozzi'.  I was actually planning on getting a Tarozzi brace but maybe I can use that one as a brace and to support my own bobbed fender.. I'll have to check the dimensions and whatnot, I'll be taking it apart and figuring that out very soon.  If it comes down to it I'll do the gl1000 swap, but I'd like to try to just add a disc and caliper to the setup I already have first.

Thanks for the advice.. you guys are the #$%*ing tits.

[garygnu]

Cue the slasher flick scary music.. reee!reee!!reee!!



Had to cut into the support bracket a little to get the hoop right for the seat length but that'll actually work out well for a spot to mount the rear blinkers.  Also, the DCC 'slugs' didn't fit at all and I had to spend a bit of time grinding them down with a drill press and an angle grinder.



Here it is mocked up with the seat before welding..





I'm not the biggest fan of the 77 tank with a bratstyle seat.  I might put some knee dents in it to see if that helps or else go with a smaller, earlier model tank.  I already have a tank from a 74 cb450.. maybe that'd work.

Anyways, got my electronics tray and oil can in from Cognito Moto.. I have to say pretty happy with almost all of the workmanship.  Everything feels really solid and I like the lines of the can.  I like the cap and drain plug on the the oil can a lot.



Some of the welds could use some work tho.. maybe I can clean those up with a grinder?





So that's where I'm at.. I'm fixing to get a Hondaman fuse block and a new reg/rec unit this week.  Does anybody have any thoughts about mounting all the electronics to the steel electronics tray?  Any pics? 

Thanks!

[SOHC4 Cafe Racer Fan]

I can relate to your feelings about the K7-K8 gas tanks. I'm not a huge fan of the lines, hence why I swapped to an F Super Sport tank with knee dents.

[7aliveatlast7]

What tires are you running on this, they look nice.

[AintNoEasyWay]

Nice choice with the Cognito Moto parts!