I screwed around with it, but didn't want to risk damaging the cam at the time. Too much of a rush to button it back up and no decent vise to clamp it up at the time. Maybe when I get back in there again I'll do it, but it ain't comin' apart again just for that at the moment.

Right now I'm dreaming of the 351 kit if I can afford it in the spring...

 

i agree for cutting the cacr. I ve done the same without facing any problems. It starts ok although i think after cutiting the cacr you shorten the life of the starter...

 

can i ask a silly question? i have manual cam chain tensioner with spring and screw. How do i know that i over tighten the cam chain? it will make noise?

 

Not a silly question. I don't know about any spring on any manual tensioners. Got any pictures?

With a thru bolt type manual tensioner, like I make, it is how it is adjusted cold, turning it in finger tight, backing off about 1/8-1/4 turn, then lock it down tight. If adjusting when hot and running, the bolt should be backed out until it starts ticking (also may feel a tapping), then turned slowly in until the ticking is gone (tapping quits at about the same point). Those will make the adjustment virtually perfect.

 

Well, if comparing the ease of spinning the engine has any value and my 650 is any indication, the 250 starter should last well over 100,000 miles. That poor starter on the 650 has to work it's bearing ***** off to crank that thing over, yet it still does the job fine at 47,500+ miles. The 250 spins like nothing is there! I'm not too worried.

 

i will post the pics later...

its more like a modification of the stock tensioner using a 6mm screw. In the end of the screw a small spring is making contact between the end of the screw and the internal side of the slider's pusher. The spring is thinner than 6mm, length about 1,5 cm and it is quite hard.

i will do exactly as you told, turn on the screw by finger until no longer can and then back just before the ticking noise.... klx678 i appreciate all the help, thank you very very much, sure you know what you are talking about.... Soon i will post all my pics and possible a dynochart

 

If the ratchet mechanism has not been taken out if you over-tighten it the ratchet will not let it back out, the chain will likely be overly tight. The engine will be quiet, but that isn't the real issue, proper cam chain tension/slack is the issue. If the cam drive pulls down on the cams far enough the film of oil that is the bearing mechanism for the cam journals caan be broken causing cam to head bearing surface contact. Metal on metal is not a good thing - partial seizure damage can be the result. Tightness can also lead to accelerated chain and slider wear too. If the spring is exerting too much pressure that also can create a bad situation.

With the manual thru bolt tensioner the chain is not overtightened unless turned tighter with a wrench. Even the strongest person cannot really tighten a bolt over about 1 lb-inch, they'd tear the skin off their fingers first. Besides, the mechanical fact is that chains should not run tight. Perfect tension is zero (0) tension, a slight bit of slack better than being tight.

In the cold set I described that bit of slack allowed by backing off the bolt from tight is to allow for the few thousandths of thermal expansion as the engine gets hot. When it is hot the ticking in the fine tuning or hot set is the play in the cam drive making the slide tap against the tensioner bolt, when tightened till it just goes away there is little if any tension on the chain and the slack is all adjusted out with the engine at normal thermal conditions - hot.

When I did a conversion on my 650 (which has the adjuster pretty much centered where the 250 does not, I drilled and tapped the body and put a bolt/lock nut set up on it, same general idea of what I do now.

 

the rachet mechanisme is off, its just the OEM tensioner's housing, the OEM tensionner's pusher, the spring, the screw and the lock nuts.

seems that i had it over-tightened...
i did as you told, all perfect, just a little tikking when cold start, after seconds goes away... Thanks again for the advice....

 

i finaly saw the AFR with a 4 wire narrow band 02 sensor (from my car) and a voltmeter, at 2500 ft

before connecting the two cables of heater (the one to 12V and the other to Ground), there was no voltage signal at all. After connecting the heaters, i saw 0.3V at idle (very-very lean), 0.85 volt at mid throttle (wich is ok, a little bit richer but safer for the engine), and 0.90V at full throttle (wich is again ok, a little bit richer).

My carb settings are dynojet stage II kit for klx 300 (the bike is 250E3), jet needle 3d position, Dynojet 132 main jet and pilot screw 2 turns out.

i turned the pilot screw one turn more out (sum 3 turns out) and the idle AFR came to 0.5 volt (ok for idle, i think).

the bike has no lidle, K&N filter, reprofiled cams, MCM only to the inlet cam, ported head and custom exhaust (header and box).

after about 1000 km i report that the bike goes much better than it was stock with 78mm piston, i could not believe the power, goes like klx250R (30PS klx250 D1, D2, D3). At last the bike has the power i want both for dirt and tarmac, I realy dont need more power........ Its excacly the way that sould have been stock from kawasaki..

thanks again marcelino and klx678 for all your helpful advises......

 

Just got done with the MCM mod. I think I got it after cross checking with other's pictures. I am at TDC with no tensioner. What do you think?