Author Topic: Top End Work Complete - Bike Won't Start (Read 6334 times)

dave500 · « **Reply #25 on:** June 17, 2011, 02:21:32 pm »

a quick check for bent valves,have only plug #1 installed and kick the bike(ignition off),can you feel it compress as it spins?does it hiss from the intake?,next remove plug #1 and fit it to #2 and try it again,does it compress or hiss from the intake on compression,do the remaining cylinders,a rough test,dont confuse intake suction with a hiss caused by a leaky valve.

Bwatson · « **Reply #26 on:** June 17, 2011, 08:01:38 pm »

I did a refresh on my 350 twin recently and couldn't get it started, stuff seemed like it was 180 off. I was puzzled on what I could have messed up, ended up being the points advancer, I had taken it apart to clean and lube it and put it in 180 degrees off.

mbspark · « **Reply #27 on:** June 18, 2011, 11:09:56 am »

well after 24 hours, I'm feeling a little better. Damage isn't as bad as I thought it was. Looks like I'm only out a few connectors and will have to do some splicing with new wires. Positive note, I will know the wiring on this bike better than I had planned.

I didn't touch the points advancer at all, so I doubt if that is off.

I'm going to go out and try your method, Dave, of seeing if there is any hissing with the intake valve in one of the cylinders. Luckily I can do this test with no ignition since all of that is fried chicken

Thank you all for the support so far!

mbspark · « **Reply #28 on:** June 18, 2011, 03:51:42 pm »

So I couldn't hear any unusual hissing coming from the bike when I tried each cylinder with a plug in it.

I noticed that when I kicked it with the carbs on, is when air would puff out the back of the carb against my hand.

I pulled off the carbs and the intake sucked in air on each cylinder. So now I'm starting to think there is an issue with my carbs, even though they worked on another bike just fine.

Why would air puff out the carb, but suck air in when carbs are off? Is that how these things are designed?

dave500 · « **Reply #29 on:** June 18, 2011, 09:06:12 pm »

you said it was running fine before the top end was reconditioned,the carbs should be ok then,somethings up with the top end,can you get hold of a compression tester?you can get cheap ones thatll work ok,you didnt cross over the coil primary yellow and blue wires maybe?

mbspark · « **Reply #30 on:** June 19, 2011, 07:49:56 am »

I will seek out a compression tester and try that next.

Results to follow.

mbspark · « **Reply #31 on:** June 21, 2011, 08:05:09 pm »

Got a compression tester today.

Came home and zip, zilch, zero. No compression. Guess that's my problem.

I tested the other 550 next to mine and it registered readings of 90 so at least I knew the tester wasn't broken $:-\$

dave500 · « **Reply #32 on:** June 21, 2011, 09:53:27 pm »

pull the head,you might have bent valves with the cam being timed incorrectly.

mbspark · « **Reply #33 on:** June 21, 2011, 10:00:27 pm »

That's what I'm afraid of. Oh well, I have all the tools I need now.

I might as well get new rings while I'm at it, so I can rule that out as an issue as well.

mbspark · « **Reply #34 on:** July 07, 2011, 07:11:43 am »

Definitely have bent valves.

Should I worry about the valve guides as well? Not sure how to check them for wear.

dave500 · « **Reply #35 on:** July 07, 2011, 12:36:55 pm »

if the valves wernt bent to an extent to jam them in the guides they should be ok,bummer man!,any time i put any engine together ill rotate it by hand to make sure this dosent happen,,the starter motor isnt so forgiving,buy new or find good used valves(how many bent?),keep the unbent ones in the same places and with an oiled guide try the new valve in the guide,raise it off its seat about how high it would lift by the cam,wobble it back and forth there will be a little movement but shouldnt be obvious or flex the guide seal,you might have to get seats cut with new valves,old ones you can be lucky and they go straight in,,good luck.

MRieck · « **Reply #36 on:** July 07, 2011, 04:53:06 pm »

Quote from: mbspark on July 07, 2011, 07:11:43 am

Definitely have bent valves.

Should I worry about the valve guides as well? Not sure how to check them for wear.

If they are really bent it will crack the cast iron guide forcing the valve out. You may have to cut the stem off just above the guide. You have to be careful installing the cam cover on 550's....it is very easy to bend valves.

dave500 · « **Reply #37 on:** July 07, 2011, 11:00:57 pm »

ive found that if you rotate the engine just after 2/3 fire,you dont have as much trouble squareing the cam cover down,start with the four bolts under the breather cap,dont winch down on the four forward short screws on those little ears next to the tappet cover caps untill the cover is almost home,have all the tappets backed right off,i dont use rubber bands just my hands,make sure the rockers arent binding/hooked up wrongly against the valve stem,time your engine,then roate it slowly three of four times by hand and check your marks each time watching the rockers open the valves and closing,feeling for a valve clash as you go,once you hit the starter its too late for errors,sorry you had this trouble,you can hold your head high and say youve been through it now.

mbspark · « **Reply #38 on:** July 08, 2011, 10:39:59 am »

yep, this is the best way to learn!

I'm going to take some pictures of the all the valves lined up to see how badly bent they are.

I guess I will be looking on ebay for some new ones. Thanks for the info on putting that cover back on, that's what scares me is that I'll just end up bending them again.

dave500 · « **Reply #39 on:** July 08, 2011, 02:25:22 pm »

it appears they got bent from the incorrect cam timing not the buttoning up of the cover.

mbspark · « **Reply #40 on:** August 24, 2011, 07:47:18 am »

Finally back to working on my bike.

I got 4 new intake valves seeing as how the others were bent. The exhaust valves didn't seem to be bent and moved well enough inside the valve guides.

Which leads me to my next question. I got everything buttoned back up with the new valves and ran a compression test and finally I have compression in all 4 cylinders!! So that is improvement over last time. Question is, I got a reading of 90 in alll 4 running a dry test. They all matched perfectly. Is this a good thing? I read on here that 120 seems be ideal. I wasn't too concerned that at least all 4 were equal.

Tonight is piecing back together the wiring from when the fire happened and seeing if I can get the bike to fire up.

mbspark · « **Reply #41 on:** August 25, 2011, 11:16:22 am »

Just thought I'd share...if anyone will even read this...I got the bike up and running and actually took it the 20 miles into work today!

What a great feeling finally getting to ride the bike after putting so many hours and money into it.

#1 carb is leaking a little, so I need to figure that out, but I couldn't help myself but to drive it into work today.

Thanks to all who responded to my questions in this thread and helped me keep the faith after bent valves, fire and heartache.

dave500 · « **Reply #42 on:** August 25, 2011, 12:47:44 pm »

a bit like a toyota?oh what a feeling.

KingCustomCycles.com · « **Reply #43 on:** August 25, 2011, 12:58:03 pm »

90 is OK to start with. You will hopefully see those numbers rise as the rings and cylinder break-in and seal to each other through wear of the natural high points.

mbspark · « **Reply #44 on:** August 25, 2011, 02:01:13 pm »

well murphy showed up at work today. Took it to lunch, started right up, rode to get a sandwich. Bike stalled on the way into the parking lot. Wouldn't start after that. Co-worked came with his truck to rescue the bike.

Tank is putting out gas, so somewhere in the carbs I have an issue. I may have flooded it trying to kick start it. Wasn't sure what else to try. I will find out when I get home. It will probably start between now and then as it will have time to sit and evaporate.

TwoTired · « **Reply #45 on:** August 25, 2011, 02:13:11 pm »

Check you battery voltage.

Maybe you have some more wires to fix. ...Or a rectifier, or a regulator...Or
No spark without a good battery.

mbspark · « **Reply #46 on:** August 25, 2011, 02:18:06 pm »

Yea, after doing some searching on here, it looks like things point to bad battery. The battery was extremely low, barely lighting up the indicator lights.

Would that cause the stalling. Not sure why it was stalling into the parking lot. I can see how that would cause it not to start up, but confused on the stall.

TwoTired · « **Reply #47 on:** August 25, 2011, 02:31:38 pm »

The charging system doesn't charge the battery at idle RPM. The bike then relies more on the battery for spark voltage.
Battery weak, weak charging, weak spark->no spark, no engine.

Best to check the bike system loads or any changes from stock, 3 ohm coils, higher watt headlights, etc.

When you get the battery weak, turning off the headlight can extend the ride. If you don't have a light switch, then take out the headlight fuse. That saves 4-5 amps of electrical load.

Cheers,

mbspark · « **Reply #48 on:** August 25, 2011, 03:39:36 pm »

Sure enough, got the bike off the truck, hooked it up to the battery charger and vroom started on first kick.

Looks like I will be doing some drainage testing tonight. The battery should be fully charged after a solid 20 -30 min ride on interstate, so something is causing it to drain. I'm guessing a fallout of the fire burning wires and me putting it back together.

bjatwood · « **Reply #49 on:** August 25, 2011, 07:44:06 pm »

Been following this thread with great intrest. I haven't built a motor yet that I didn't have to massage a bit after intial assembly. You will know this bike more intimitely than a Honda assembly line worker! LOL
Seriously tho, you did what you had to do, kept at it and kept putting out the fires that pop up, and that first coversation or nod from a passerby will make you realize that all your hard work was worth it, and when you twist that throttle up to 8K and that baby makes music, the hair on the back of your neck will stand up, and that smile will be from ear to ear. Priceless!

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Author Topic: Top End Work Complete - Bike Won't Start (Read 6334 times)

Bwatson

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KingCustomCycles.com

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