Another one...

[loganm]

Are we taking bets this time? Finished putting it together today. New head studs, bore, piston, gaskets, and some (very) mild carb porting.

Turned the idle speed up all the way then backed the air screw out until it would idle on its own. Upped the main to a 160 (from 140, stock is 152) for break in, mixed at 20:1. I know, "oil technology improvements bs", but I'm not taking any chances, it's what the manual recommends anyways.

Let it idle for about 15 minutes with a fan on it. It's humid and 70ish today, didn't get very hot at all.

https://youtu.be/EpNZPIbBJrA

[averysdad]

How hot was it ? I have a temp gage like that if I remember correctly mine gets up around 300f seems pretty hot to me. Maybe my 15$ gage isn't accurate. Smells hot from time to time that's when I shut it off lol. How hot should the air cooled 250r run?

That one sure sounds a lot different than mine?

[loganm]

It was around 130F. It should idle around 155F with some airflow on a cool day, at least in my experience. 300F is close to seizing on mine. It sounds different cause there's no silencer. Not riding it until I put one on.

I'd shut it off immediately if temps get to 300. Obviously you can't watch it while riding hard, but if it's close to 300 with easy riding that's not good.

[JesseA420]

[averysdad]

I think it was 300f I'll check next time I ride it I know I can't touch the jug for more than 1 sec. Its jetted on the rich side on the pilot and main as far as I can tell don't know why it would be running hot? I never really ride it easy and there's never really a cool day in Houston tx lol.

[roostin atc]

Leak down test first, then jet. Log jamming lol

[yaegerb]

Running hot is relative unless someone can produce heat tolerances for an air cooled Honda. I will admit I haven't searched for such literature but you may be able to drop a note to Selvy, Carlos, Klemm or hall and they might be able to tell you. It might also be worth investing in a trail tech temp gauge. I have one on my shee and my rule of thumb is if it gets above 190, shut it down. All motors are different and I would venture to guess an air cooled 250r has a wider range of heat fatigue than its water cooled cousins. If you don't want to invest in a temp gauge then keep reading your plugs. And another item to note. Air cooled motors don't do well sitting unless you have a massive fan blowing air over the fins. When I heat cycle a freshly rebuilt air cooled motor I have a huge industrial fan blowing on it at high speeds. Keep it moving, read your plugs or get a temp sensor and it should last you a while.

[loganm]

Well, RELATIVELY, I seized the top end up at (I'm guessing) ~325F. I know I have seen it still running at 300F. If it seizes up solid and is too hot to touch, and you pull it apart and there are signs of a piston seizure...

I'm not running a leak-down test rn, I was thorough enough when I built it.

[yaegerb]

Well, RELATIVELY, I seized the top end up at (I'm guessing) ~325F. I know I have seen it still running at 300F. If it seizes up solid and is too hot to touch, and you pull it apart and there are signs of a piston seizure...

I'm not running a leak-down test rn, I was thorough enough when I built it.

I wasn't responding to your post, I was responding to averydad's post. And honestly I could give a shite less what you do with your bike.

[loganm]

I wasn't responding to your post, I was responding to averydad's post. And honestly I could give a shite less what you do with your bike.

Except beat you in a race >_>

[bkm]

To answer your question, and since you touched it, I'd be surprised if it made it back to your house.

Sent from my SM-G900V using Tapatalk

[Onetrackmind]

Except beat you in a race >_>

Oh good. YOU'RE back.

[averysdad]

Thanks for your reply yaegerb. I thought Loganm grow up and was done with the rude I know every thing teenage drama. I just wanted to talk air cooled 250r s and he just wants to be disrespectful to people trying to help the both of us that's messed up. I'm not looking at this thread any more its going to be a soap opera just like the last one.

[Scootertrash]

The Top End Terrorist returns..............

[tripledog]

Except beat you in a race >_>

<_< To buy yet ANOTHER piston.