My 78 CB750F3 Super Sport Project

[Hoko]

This pic is after I have had the bike for several months now and have done a lot of cleaning and armoralling the plastic stuff (soaked it up like a sponge).  Unfortunately I didn't have a camera when I first bought it so you could see it after it had sat on the PO's driveway for 5 years without being started!  Needless to say it was pretty sad looking!  I was doing some work for the PO and told him he had a great bike (I knew it had potential and I grew up riding hondas in the 60's and they've been my favorites ever since).  He instantly said "You want to buy it?" His wife was definately anti-motorcycle and didnt want him riding it, so I thought about it and said "How much you want for it?"  He said it ran great before he parked it except the charging system had quit and he had all the wiring replaced before he parked it, which was $400 and he would sell it for that.  I said "You got it!"
     Everything is pretty well intact except for quite a bit of rust has set in which I will eventually have to address.  I'm starting with the carburetors which are siezed up as far as throttle and sliders.  I want to get it running so I can check the cylinder compression to see what kind of shape the engine is in.  I finally am getting some time to work on it so I will post as I work through it.

The throttle bar is completely siezed up and the sliders in the back of the throat are frozen as well.

The boots on the airbox were loose when I took it off and one of them was torn so those will get replaced.  The boots from carb to engine were stiff and clamps were worn also so I'm replacing all of them so the whole system will be well sealed.

I made a tank with plexiglass and silicone to soak the carbs in about the size of the carbs so I wouldn't have to buy any more of that Chem-Dip ($30/gal!) than I have to!  I should have some time this week to pull all the rubber and gaskets out so I can dip it for a week.---UPDATE--- About 10 minutes after I put the Chem-Dip in the tank with the carbs, it started leaking.  The plexiglass is fine but the Chem-Dip is destabilizing the silicone caulk and it is causing it to let loose of the plexiglass.  So I went to Target and found a plastic container that looks like it will work.

[pat english]

dang thats beat bro!..jk..pretty good shape for what you paid for it...if youre intake boots are not cracked,you might wana consider doing that carb boot restoring trick.those boots are $90 brand new..i forget what the proceses is(someone will chime in on exactly how to do it),but i hear its makes them soft and flexible like new and works fast..i personally just soak them in oil for a month or so...ask tools if it works,i just sent him a set of intake boots that i had soaking for a while.

thats a pretty sweet box you made,but if you lay the carbs down you will be able completely submerge the carbs with 1 gallon of dip..

also,didnt i send you a seat?youre seat looks a hell of a lot better then the one i sent..i feel bad now. if you need anything else,and i have it,you got it.

[LukeM]

Wintergreen oil in water.  TOOLS will remember the ratio, but it works well.
My son's carb boots were cracked on the inside, and I was thinking of lining the inside with a very thin layer of RTV silicone.  Then again, I wouldn't want any of that flaking off and getting in the engine.  Might work OK on the outside.  

Luke M

[Hoko]

lol, if you saw the seat up close you can see it is cracked bad, wouldnt even last a month before it starts to shred, I just sprayed some armorall on it for the shine so I wouldnt have to look at it while working on it, not to mention the cleats that hold the seat cover on the bottom of the seat were rusted off on one side.  yeah maybe I'll be able to lay the carburetors down after taking float bowls off.  good idea Thx for the tips for softening the boots!  Probably wouldn't hurt to take those boots off every 2-3 years and soften them up.

[pat english]

hey,i used some of that plastic weld 2 part epoxy on the intake boot of the cm 250..it was cracked..now its all good..

[pat english]

oh right on..well still,you need anything,let me know..

2-3 years?those dam boots last 30 years!..i think if you softin them up again,theyll probly outlive you.

[Hoko]

When I took the air box off the carbs yesterday I wondered why they fit the carbs so loose.  Today I was looking through the FSM and I realized they were so loose because the PO was running it with no clamps on the boots!

[pat english]

thats strange..you need those clamps!

[Hoko]

Yeah, that would explain why the air filter was so clean

[Hoko]

These little fellers were pretty gunked up.



One of them didn't have the varnish in it but had rust in it like it must have had water in it.



See the Float Needle Seat?  How do I remove that and install a new one?  I'm thinking this one is not removable, it is round and flush with the carburetor casting like it was pressed in.



It may not be a small container but its the closest size I could find to the carbs. (used 2+ gallons dip)  I'm just glad to get the ball rolling.  Gonna leave them in there till next Monday. Now I just need to find some carb kits.

[pat english]

hey looking good bro...tools will know how to get those jets out...he seems to know everything..

take those carbs out after 2 days or so and try to get things to move..my stuck throttle valves came out 1 at a time.

[Hoko]

Ok Pat, THX!  Ordered carb kits, should be here before carbs are done soaking  Think I'll just slap some pipe clamps on those airbox boots and replace the boots later.  I was thinking I would replace the float needle seats but these are round not like those replaceable hex jets and look like they were pressed into the casting since they are flush with the carb casting.

[Hoko]

I saw a carburetor assembly like mine for sale on this site http://www.motorcyclecarbs.com/CARBURETOR_KIT_HONDA_CB750F_K_P9270C646.cfm      I clicked on buy just to see how much they wanted for it      WO! $800  

[shinyribs]

LOL> I have seen some crazy prices for parts on these bikes. Some guys are nuts. Are you sure you need to replace those seats? If they are smooth and dont have gouges or a wear ring in them they might be OK. Good luck with your carbs Batman

[pat english]

those look like the cr carbs.

[Piute]

pat english wrote

those look like the cr carbs.

   I think there stk. carbs Pat, look same as mine.
But what the hell I'm just bargaining to fine tune mine,
  Miles N miles in between tune-ups

[Hoko]

shinyribs wrote

LOL> I have seen some crazy prices for parts on these bikes. Some guys are nuts. Are you sure you need to replace those seats? If they are smooth and dont have gouges or a wear ring in them they might be OK. Good luck with your carbs Batman

You know, I am just a noob and will do anything someone says I should do, haha so I guess I should just put it together and see how it runs!  Anyway I am learning as I go and it really is a lot of fun since I like gearhead stuff.  That Batman stuff gives me an idea.  That would be downright bodacious to make a batcycle like the one in "Batman Begins", that was one awesome bike.

What do you say, We team up and build this bike!

[Hoko]

" Check your connectors:  if you used crimped wire connectors, try soldering them, as crimps can fail, easily."   Sarge

That would not be good if that happened here.  Is there any way to organize this pile of spagetti?

[pat english]

it did happen there...you got alot of wires added into that mess..someone has fucked with youre harness..might be a good idea to just buy a new one.i think theyre around $100..well worth the piece of mind knowing youre bikes not guna burn down.

[wes]

that wire mess looks alot like mine. i had to look for fuse panel. i found it behind headlight in box. pat, you say you can get a new harness for around $100? where might that harness be? it would be nice to have a new one, im on a shoe string budget these days. every thing on the bike works, im wonderin if i should just leave it as is. maybe i should get brakes workin right first... so much to do... so lil cash.