It's been at least 10 years since I've ridden a bicycle....
problem... Specialized Globe "comfort" bike..ok, that' what the guy in the shop said it was...I bought it sometime in the 1990's ( I think)
When moving,, the movers (having more muscles than brains) simply turned the handlebars sideways to fit in the shipping container better.
Fast forward 5 years... now I'd like to ride the bike.
Problem. the handlebars now will not stay when I adjust them. The centerpost (forgot what you call it) seems tight, but I can't tighten the hexnut enough to keep the bars in one position. They start out fine, but I can yank the ends of the bars up and down at least 5 inches. Makes for interesting stopping...I'm not very good at riding to begin with, and old age hasn't helped...
Oh, the stem does not move...only the Handlebars. The 6mm nut is nice and tight, no twist sideways.
I can tighten the hex nut under the handlebars, and all seems tight, but it won't stay... Don't want to overtorque it, I've ...umm......accidentally twisted off/broken a few bolts on my motorcycles...
riding is fine until I lean forward to stand on the pedals, then the bars drop down....they don't twist, just drop. (Yeah, I'm pbly riding incorrectly...<G>)
There is a hex bolt that is facing the sky on top of the stem. That is how to adjust the height of the stem. You might need a longer handle L shaped hex wrench for more torque to free up that hex bolt in the bottom of your photo(that bolt adjust the angle of the stem). If you tightened the bolt on top of your photo all the way and the bars move around, then you got a problem. Is the brake levers/shifters moving or the bar? There are some very tiny hex bolts that you need to tighten for them to stay in place.
BTW, your stem is a tad bit too high. I can see the minimum insertion mark that you should not see for safety reasons.
I'm afraid of overtightening it....
I was wondering if the twisting sideways when the bike was shipped could have messed up the handlebar clamp....
Ok, and the 4 small hex nuts (that I cant' budge) allow the stem to adjust...?
So the handlebars are twisting in the stem, right? If so, your arrow is correctly pointing to the bolt you need to tighten.
Your stem will adjust up and down. You need to loosen the lower bolt from your picture (and possibly one on the side) and that will allow the angle of the stem to change. It looks like its about as high as it goes currently.
The other bolt (on top, under the plastic cap) is what tightens the stem to the fork. This should have been the only thing the movers needed to loosen in order to twist the bars sideways. It does look like the stem is now raise too high (see the ring of marks around the stem where it goes into the frame/headset? That is probably the minimum insertion line. Loosen the top bolt, slide the stem down to where that line is hidden, and retighten the bolt.
'08 Fuji Roubaix RC; '07 Schwinn Le Tour GS; '92 Diamond Back Ascent EX
From the first pictures you posted, it looks like there is room for the clamp to tighten further and the bolt with the arrow pointing to it is the one to tighten. The others are correct, it looks like the stem needs to be lowered to below the minimum insertion line. Not sure on your particular stem but the adjustable ones I've delt with needed to have the bolts on the side loosened when adjusting.