Topic: Newbie questions about K0 seat and.........

[techy5025]

Hello,

New to posting but not new to the forum...great advice.  I have a couple of questions for the experts. 

1.  I replaced the seat on my K0 with a new seat off ebay....correct for the year but not an original "ducktail" seat.
I have the original .... the cover is fine (no rips), but the foam is shot.  Does anyone sell pre-fabed foam? I suspect
any foam from a used period seat would be as bad.  The local auto seat shops don't want to touch the job.

2.  I searched the archives for pro's and con's to silicone brake fluid. Lots of discussions about brake bleeding and such
but no discussion of Dot 5..that I can find.

3.  I have replaced the carbs with (I think) K3 ones with integrated pull.......because my original K0 carb floats have pin
holes in them.  Are the floats obtainable by themselves....the rest of the carbs are fine.  I would like to go back to the
original ones if possible.

The bike missed being a sandcast by a few hundred serial numbers.   If I had known in 1970 when I bought it, maybe I
would have looked for a slightly older bike. 

Thanks for your help!

Jim

[nomadwarmachine]

Steer clear of the DOT 5 stuff, no good for these systems, though the 5.1 is supposed to be acceptable.  I use the Dot 3/4 -- there is a limit to the effectiveness of these old brakes, which you can augment with braided steel lines and such, though short of going dual-disk, you are never going to come close to a modern three-pot Brembro, or the like.

[Jonesy]

Floats are still available, although they will be the new plastic ones that almost never go bad. Those should fix you up.

[Clyde]

Have you tried using the floats from the K3 carbs?
I would do as posted before and replace them with the later plastic ones. Because they do last forever you could look for a second hand set.
In my opinion the older carbs look right on a K0. Even if they do not hold their balance as long as the later ones, I would use them.
I use silicon brake fluid with my bikes- no problem if you change the master cylinder kit and piston seal. A lot harder to bleed properly than normal fluid. The only reason I used it was to avoid paintwork damage on my repainted F1 and Z1 calipers, otherwise I would have continued to use DOT-3/4

[MikeDeB]

1.  I replaced the seat on my K0 with a new seat off ebay....correct for the year but not an original "ducktail" seat.
I have the original .... the cover is fine (no rips), but the foam is shot.  Does anyone sell pre-fabed foam? I suspect
any foam from a used period seat would be as bad.  The local auto seat shops don't want to touch the job.

2.  I searched the archives for pro's and con's to silicone brake fluid. Lots of discussions about brake bleeding and such
but no discussion of Dot 5..that I can find.

3.  I have replaced the carbs with (I think) K3 ones with integrated pull.......because my original K0 carb floats have pin
holes in them.  Are the floats obtainable by themselves....the rest of the carbs are fine.  I would like to go back to the
original ones if possible.

Welcome to the board.

1. David Silver sells a seat cover and foam kit for the K0 that replicates the original "ducktail".  It's rather pricey at around $125 (not including shipping).  Classic Motorcycle Supplies sells a complete seat that is a repop of the original "ducktail".  It's priced around 159 euros.

2. Unless you're racing and heating the caliper up to around 400 degrees F you shouldn't have a thing to worry about using DOT 5 silicone brake fluid.  But, it is very important that you either replace all the seals with new ones or clean the old ones very thoroughly in denatured alcohol.  Even if you replace the original seals you should still clean the rest of the brake components (lines included) in denatured alcohol.  DOT 3/4 and 5 should never be mixed.  I used DOT 5 on one of my previous bikes and found that it worked just fine and bled just the same as regular brake fluid.

3. As posted before use the newer ones on your original carbs.  You'll have to experiment with float settings as Honda didn't specify a float height for the old brass ones.  One of the listers measured his at around 30mm.  The newer ones are set at 26mm.

[kaysystems]

3. As posted before use the newer ones on your original carbs.  You'll have to experiment with float settings as Honda didn't specify a float height for the old brass ones.  One of the listers measured his at around 30mm.  The newer ones are set at 26mm.

I always assumed that since the only difference between the K0 & K1 carbs was the push-pull linkage, then the float heights would be the same. The manual shows a K1 height with brass floats at 26mm.

Is 26mm too high? Perhaps not with new needle jets & needles. Your opinion would be appreciated to help get rid of the black plugs.

Thanks

David

[Bob Wessner]

I used 26mm for the floats (brass origs.) on my K0. Seemed to be the correct setting. I did have to tweak one as it had an intermitant overflow leak, but I think that might be more because of the ruler method I used rather than an accurate gauge. Read that as my bifocals played tricks on me. 

[techy5025]

Thanks..........

for all the helpful replys.  I am going to use the Dot 5.  I have used it in all my cars with good
results and couldn't understand the reluctance to use in bikes I was getting from some
people.  I am going to replace the two hoses and the brake pressure switch along with
seals.  I am somewhat undecided on the stainless jobbies....maybe if they come with a
rubber "overcoat" to look more original.

As I don't need the seat cover, I am reluctant to buy a kit of both it and the foam.  I'll
keep looking for just the foam.

I have replaced the spokes with stainless from Buchanon and they look great....bigger in
diameter than the originals though.  Learned more than I wanted to know about lacing!

Now if I can just get my polishing skills up to par.

Now that I am retired,  I am riding the bike a lot more.  It sure draws lots of attention,  but
getting pulled over by the cop the other day who only wanted to oggle it was a bit much.

Again Thanks.......

Jim

[martini]

Hey Jim,

I just acquired a K0 myself, not a sandcast but still a great bike. I'm rebuliding my original carbs from the ground up, complete with new plastic floats. Hopefully that will turn out to be a wise decision because it has cost me alot more than a decent replacement set from a newer model on e-bay.

I have the same issue with the seat as you. I have a brand new cover but my existing foam is not up to the duck tail. Have you had any luck finding just the foam?

Cheers,
Shane

[jaannaktin]

My K0 seat looked smooshed like a banana -- its currently at a local reupholsterer -- I'll let you know how it comes out. I was quoted 150 dollars for a whole seat rebuild, including blasting and repainting the pan, new foam and repair of a small tear in the vinyl. cheaper than the 200 plus euro seats on cmsnl and other sites. I'll ask them what kind of foam they are using. The old stuff crumbled like a sick cookie.

Jaan

[kghost]

Just to beat a dead horse............

I used Dot5 in my last build. With new hoses, seals, Master cyl. Kit. No Problems, works as good as ever.

If your handy with a micro torch and solder you can solder up the pin holes in the stock metal floats.
If you use the composite floats and want a perfect float level, you can make a set of tools to do it. On mine I wacked the overflow tubes out of a set of bowls and put some clear tubing on the nipple. Now I just put the modified bowls on the rack of carbs, Run gas in them, look at the clear tubes. Presto, I know which fuel levels are high, which are low and which are good. Ajust from there.

Yeah, Cops. Two Cars pulled up at the diner I was at the other day. Cops started walking around the bikes (2). Thought there was going to be a problem. There was!

Cop number 2 needed a set of coils for a 73 750!

Yup, I have him one of my old sets. Never know when you might need a freind at the station.

[techy5025]

Wow...kghost...that is a clever way to adjust the float levels.  I will have to try that!   I have one that on rare occassions
leaks a little.

I am going to try calling some local seat upholstery people tomorrow to see if they want to replace the foam in the
original ducktail seat.  I have a new "almost correct" Honda seat on now, but I would like the original back on.

Jim