Hawk 250 first start problems

[psychprof]

Originally Posted by OneLeggedRider

I'm surprised folks are so wary about doing such a simple screw and locknut valve adjustment on a single cylinder 2 valve head. I think I learned that when I was about 11. Even before I went to MMI I was doing multi valve shim under bucket adjustments on inline 4s where you had to keep going over to the bench grinder because you didn't have all the proper shim sizes and you wanted to get your buddy back on the road.

I think it's because of several factors.

1. Stories like the one guy who had a smashed spark plug. Even he asked if it has due to the valve job he did. I understand people here felt it was unrelated, but it can be worrisome for some folks.

2. I'm guessing that most of us have not gone to MMI. Many of us like to tinker, but maybe some of us are new to opening an engine.

[Megadan]

Originally Posted by psychprof

I think it's because of several factors.

1. Stories like the one guy who had a smashed spark plug. Even he asked if it has due to the valve job he did. I understand people here felt it was unrelated, but it can be worrisome for some folks.

2. I'm guessing that most of us have not gone to MMI. Many of us like to tinker, but maybe some of us are new to opening an engine.

His point is, - These are about the best engines to learn this kind of stuff on, and there is plenty of information and even people willing to help for those that have maybe never done it before. It doesn't get any simpler and easier than this.

[OneLeggedRider]

Originally Posted by Megadan

Welcome to the uni-cam head design of the VFR1200F, with shim under bucket intake valves, and a roller rocker solid tappet exhaust actuation that has two clearances to set, cam side and valve side.


I would gladly do 100 Hawks before doing this valve job again. That is the easy to reach rear cylinder head.

Dan I've never had the pleasure of doing that particular one lol, but I do think I read about it in a Cycle World story. I'm sure it wouldn't be much fun. Ducati has some valve trains that would rival or surpass it in difficulty though.

[Audihuff]

UPDATE! so last night we had idle. let it cool over night. now i tackled the valve clearance. got it to fire up a few times but now i cant idle again. i think i have exhausted the stater/battery, so ive been kicking starting it... so i was messing with getting it to idle with the idle set screw and it died, so i kick it again and this time IT KICKED BACK! is this normal? i hope i didnt do anything wrong

[Alpha Reign]

Did you make sure to adjust the valves at Top Dead Center?

[Audihuff]

Originally Posted by Alpha Reign

Did you make sure to adjust the valves at Top Dead Center?

yes sir, im 99 percent sure i was on compression stroke as well.. there was zero play from factory.

[Alpha Reign]

Cool. Just a small tip. Take off the spark plug and put your finger over the hole. If you feel air pushing out, that means you are on the compression stroke.

[Megadan]

Idle speed screw won't help it idle better if the idle mixture is too lean, which it usually is. This is compounded by your now properly set valves. Hard cold starting is a very common issue with the stock carburetor tuning, which is why that was also suggested.

[Audihuff]

Thanks to all your help everyone! I now am a very happy individual! All this stressing and overlooking I forgot to keep gas tank full.. as I ripped out the carb many many times I lost quite a bit of fuel. Which lead me to believe I did something wrong when it wouldn't start.. any ways 11 miles in and fun so far! Thanks again!

[Ariel Red Hunter]

Originally Posted by psychprof

I think it's because of several factors.

1. Stories like the one guy who had a smashed spark plug. Even he asked if it has due to the valve job he did. I understand people here felt it was unrelated, but it can be worrisome for some folks.

2. I'm guessing that most of us have not gone to MMI. Many of us like to tinker, but maybe some of us are new to opening an engine.

My dear psychoprof, very few of us went to MMI. Adjusting the valves IS NOT opening an engine. When you have to do a valve job because you didn't adjust the valves, then you get to experience opening an engine. I know, you can hardly wait!!!!ARH

[Sochin]

I sat my valve lash from the get go, checked and adjusted again at 100 mile, 300, 500 and then I did at 1000. After that I will check it every oilchange or 1000 miles. My runs like a scolded ape, so I must have done sumthin right?

[Landsvw]

I’ve gotten to the point that, I can run the engine up to TDC compression stroke, grab the rocker arms on the bike engine and rattle it/them (click, click, click). I can usually tell if it’s too loose. And if it’s too tight, can’t rattle. Just a simple test when fiddling with other parts of the engine. If it feels weird, then pull I out the feeler gauges.

[NzBrakelathes]

Originally Posted by Ariel Red Hunter

I like the go-no go idea. Set the intake to .003, which means that an .003 inch guage should pull through this gap with a one or two pound pull. an .004 won't go, an .002 will fall through (means no drag). For the exhaust, the .004 is our go to guage, so set the clearance so that the guage pulls out with a one or two pound effort. The .003 guage wiil pass through with no drag whatsoever, and the .005 guage tells you 'no kinda' way'...ARH

Using thou gauges IMO is a too big of a jump
mm gauges are much smaller and gives a finer increment in testing
0.01mm is less then half a thou which is 0.0127mm
So by using mm feeler gauges and using the go n go method your testing to a much smaller tolerance
Again my opinion and backed with a theory and some fact
Each to their own but that’s the VERY reason I supply mm feeler gauges in my tool set on eBay
I see and believe it’s a more accurate way and test with mm feeler gauges

[Landsvw]

Another point would be, if you’re going to err, err on the side of too open. So, If you’re using inches (btw, all my feelers have both inches and metric printed on them) or whatever (I had a Russian rifle with Arshin units for trajectory one time. Found out that an Arshin =28 inches, standardized by Peter the Great, but I digress...), then too open is way better than too tight. Rattly tappets, ok. Tight tappets, burnt valves and loss of compression.

[NzBrakelathes]

Originally Posted by Landsvw

Another point would be, if you’re going to err, err on the side of too open. So, If you’re using inches (btw, all my feelers have both inches and metric printed on them) or whatever (I had a Russian rifle with Arshin units for trajectory one time. Found out that an Arshin =28 inches, standardized by Peter the Great, but I digress...), then too open is way better than too tight. Rattly tappets, ok. Tight tappets, burnt valves and loss of compression.

That’s why I suggest the mm feeler gauges n go no go method
A little “using brain” shows you it’s within the specs and remember there’s not 1 size but a slight range so let’s say 3 thou plus or minus half a thou this would be like 0.065mm to 0.93mm and using the finer increment mm feeler gauge along with go no go gives you a more accurate setting
No more side of too tight or loose as you can self test more accurately