Author Topic: 1976 550K Project (Read 30742 times)

Stev-o · « **Reply #25 on:** October 05, 2014, 06:45:43 PM »

Quote from: mrfish2 on October 05, 2014, 04:06:39 PM

Quote from: Stev-o on October 05, 2014, 04:01:23 PM
Bet your pilot jets in the carbs are clogged.

One of the pilot jets i cleaned completely, even with guitar string, and the other 3 i had to replace.

Ok, lost that bet. Have you checked your spark advancer?

goldarrow · « **Reply #26 on:** October 07, 2014, 08:26:20 PM »

So what have you done on the maintenance list? Valves check, ignition timing check, etc...

mrfish2 · « **Reply #27 on:** October 30, 2014, 12:43:07 PM »

Sorry been pretty busy with school, but checked the timing and adjusted the points last week and got another chance to mess with it again today. Put some more fuel in the tank and she fired right up but had gas pouring out of the #3 carb. Must have a float sticking. It was weird because it didn't take long for it to idle fairly decently. Maybe it was just the points haha.

Question: when I rev it up it hangs up when I let off the throttle, like say I rev it up to around 5k it'll stay around 3-4k for longer than it should before dropping back to idle. Thoughts?

mrfish2 · « **Reply #28 on:** November 09, 2014, 04:10:00 PM »

Figured out it was a vacuum leak around one of the carb boots.

Spent the past couple days installing clubman bars and I have to say all that time spent routing the wires through the bars was well worth it. Took the front turn signals off too as they were in the way of the clubmans and aren't required in NC anyways. I'm putting the rear fender back on as soon as I get some more time to clean it up real good. Shorter throttle cables are on their way (ordered some from 4into1.com that are for a 400F but are about 5 inches shorter than the stock 550 cables so they should work well with the clubmans) along with a new chain and sprockets. After all that is installed all that's left is rebuilding the the master cylinder/caliper (I've been putting that off for a while) and a set of tires and she's ready to hit the road. I know you guys like pics so here ya go

Slinky · « **Reply #29 on:** November 10, 2014, 08:07:49 AM »

nice man, looks really good!

mrfish2 · « **Reply #30 on:** November 15, 2014, 03:08:16 PM »

Finally had some time to rebuild the forks today with new seals and new oil. It's amazing what some Simple Green, a brass brush, and some elbow grease will do.

But now he looks kinda pitiful without his shoes on

Any advice on getting this old inspection sticker off?

mrfish2 · « **Reply #31 on:** November 20, 2014, 02:41:45 PM »

Routed the new throttle cables today and ran into a little problem. The length of the 400F cables I ordered fit perfectly with the new clubmans, but the Push cable's end was too big to fit into the right hand controls (see below).

Took the dremel to it and ground around the edge to make it fit. Didn't take much, but I figured I would post this on my build thread in case anybody else orders these cables for their bike.

mrfish2 · « **Reply #32 on:** November 26, 2014, 11:32:33 AM »

Finally got the brake piston unstuck

Old brake pad

Rust in the caliper assembly

Stev-o · « **Reply #33 on:** December 07, 2014, 08:05:21 PM »

I've seen a lot worse. Remove the seal and clean that groove til it's spotless. Install a new seal.
Good time to paint the caliper too...

mrfish2 · « **Reply #34 on:** December 07, 2014, 08:14:02 PM »

I'm actually surprised how clean some parts are on this bike (besides all the rusty chrome). I'm getting some Dow Corning grease in the mail this week so i can finish up the brake rebuild, and I've already got a new seal and piston. Got the new tires mounted yesterday as well. I should have this thing on the road by Saturday (after 22 years haha) and I'll post up some pics too.

mrfish2 · « **Reply #35 on:** December 08, 2014, 04:15:09 AM »

Haha good catch, but in fact I actually mean this Saturday! I'm not saying it'll be ready to take to a show, but it'll definitely be a daily driver for me.

mrfish2 · « **Reply #36 on:** December 11, 2014, 01:47:37 PM »

She's done! (well...almost...) Got some new Dunlop K70 tires put on, brake caliper rebuilt, and finally finished bleeding the system today. New grips and mirrors curtosy of Dime City Cycles. Gave the tank a polish and wax yesterday and boy does it shine now, even with the faded paint.

Rode her for the first time today too, and man was it sweet. Then after about ten miles I came to a stop light and she sputterd and died, so I thought maybe the idle screw was too far out. Kicked her back to life, adjusted the idle screw, and went on my merry way. The very next stoplight I came to she decided to do the same thing again. Kicked her back a second time (with cars honking at me from behind) and proceeded to get home as fast as I could. I'm pretty sure the vacuum leak is back cause the idle kept hanging up, and when I got back I checked the headers to find that #4 was cool enough to touch (this being after a ~30 minute ride). Any suggestions?

The day I brought her home

Today

streak09 · « **Reply #37 on:** December 11, 2014, 04:10:08 PM »

Quote from: mrfish2 on December 07, 2014, 08:14:02 PM

I'm getting some Dow Corning grease in the mail this week so i can finish up the brake rebuild

Is that just an overall lubricant? Or used for very specific applications?

Also, congrats on the maiden voyage! If you can touch a header after a 30 minute ride, then its not fireing at all. What do the plugs look like? You mentioned an overflowing carb, maybe it is now stuck closed? I think you are on the right track with vacuum leak as well.

mrfish2 · « **Reply #38 on:** December 11, 2014, 04:17:27 PM »

The Dow Corning stuff is for the back of the brake pads where they come in contact with the caliper bodies. When the caliper heats up from being used this type of grease (pure silicone) won't run everywhere like a typical petroleum grease. There's a few threads around here that go into more details about it.

The plugs are brand new, but I've yet to pull them out. It was getting dark when I got home so the agenda for tomorrow is to figure out for sure if it's a vacuum leak or not, and pull the bowl off the #4 carb to see if anything is sticking. I adjusted the points and tappets a few weeks ago, and it shouldn't be the coils because #1 IS firing. But will a vacuum leak cause a specific cylinder not to fire?

streak09 · « **Reply #39 on:** December 11, 2014, 06:34:15 PM »

In my experience a vacuum leak is usually associated with hanging revs. I wouldnt think it would cause a no fire condition, maybe in severe cases (like no manifold

).

mrfish2 · « **Reply #40 on:** December 11, 2014, 06:40:05 PM »

Maybe it's the other way around? As in not getting fuel or spark to that cylinder might cause it to sputter and die at idle? I posted this question in the Bikes thread so more people might see it.

mrfish2 · « **Reply #41 on:** December 12, 2014, 09:57:23 AM »

It ended up being the float valve in the #4 carb, so now that pipe is just as hot as the rest. And no, I don't have a fuel filter on the lines. I cleaned and RedKoted the tank a few weeks back.

But after fixing the float valve and setting the height again I rode it for a few miles and it struggled getting up hills and misfired a lot. Like I would roll on the throttle and it would speed up, then die, then speed up again, and sometimes die a second time before finally speeding up. Definitely not the "flat spot" I've read about. I'm gonna go check the tappet clearances again to be sure, but it sound like it's a vacuum leak again.

mrfish2 · « **Reply #42 on:** December 12, 2014, 01:12:26 PM »

I readjusted all the valves and points and everything was going well until this happened...

I was hoping it wouldn't leak any oil but after idling for a few second it started to weep out, so another is on its way from 4into1.com. When it gets here I'm gonna check the timing again (didn't do that today), but after that I'm not sure where to go if the revs are still hanging up.

goldarrow · « **Reply #43 on:** December 12, 2014, 06:54:21 PM »

At least now you know your top end is getting oil

mrfish2 · « **Reply #44 on:** December 12, 2014, 07:19:24 PM »

I know a vacuum leak will cause the revs to hang up, but will it also cause it to misfire and struggle up hills? Or is this more related to a timing issue?

mrfish2 · « **Reply #45 on:** December 17, 2014, 10:11:10 PM »

Set the timing statically, got it as close as i could and I'm pretty sure that fixed the misfire. Replaced the broken tappet cover today too. It's still running on 3 cylinders, and I'm pretty sure it's a carburetor issue. I replaced the float needle, but maybe it's something else? If i leave the fuel on it'll slowly drip fuel out of the overflow lines for the #4 carb still, which indicates a float issue. I'll get it figured out eventually haha.

Question: will running lean/rich cause the revs to hang up as if it has a vacuum leak?

seanbarney41 · « **Reply #46 on:** December 18, 2014, 03:25:38 AM »

Dude, your float needle looked to be mechanically fine...but think your problems might have anything to do with your carbs being filthy? Pull them off and rebuild before wasting any more time. I am guessing your idle jet will be plugged on #4.

mrfish2 · « **Reply #47 on:** December 23, 2014, 04:15:21 PM »

Yep, you're right. Chalk that one up to my inexperience with the carburetors. The original #4 carb was damaged and I replaced it with a soda blasted one from Harisluv, so if anything is wrong it's definitely not the carb body (and now the float needle). So i can at least mark those off the list of things that could be causing the fuel flow issue.

When I get some time I'll pull the bowl off again and go over the idle/main jets meticulously, then check the needle and emulsifier tube again. If it's none of those all that's left is the floats themselves.

Edit: I replaced the #1 carb body, not the #4. So one of the small orifices could very well be plugged somewhere in the #4 carb.

mrfish2 · « **Reply #48 on:** January 07, 2015, 04:48:34 PM »

Replaced every brass piece in the carb but to no avail, she still won't fire on that cylinder. Ordered a set of OEM floats because that's the only part left to replace that might be bad. If i get the float swapped out and that's not the culprit then there must be some orifice in the body that's blocking fuel flow to the bowl.

Checked on the o-rings behind the intakes and they're soft and squishy (very surprising for being so old) so they're not responsible for my vacuum leak. I'm thinking maybe one of the clamps around one of the boots was too tight causing a boot to pinch and allow air in, that's the only other explanation i have for the leak. On a lighter side, it only took me 20 minutes to get the carbs off the bike this time haha. One i figured out the trick it's not too bad now.

mrfish2 · « **Reply #49 on:** January 17, 2015, 12:03:56 PM »

Updated a lot of the screws around the bike, including the seat buckles.

Out with the old

In with the new

Put the carb rack back on the bike today and am still trying to sort through the cylinder not firing. Pretty sure it's not fuel related anymore because the #4 plug was fouled. Might be time to replace the plug caps.

News:

Author Topic: 1976 550K Project (Read 30742 times)