MOPED ARMY

Sounds like you're running lean and soft seizing. Have you replaced your crank seals? I betcha didn't....

Replace seals, Put in a fatter jet, or better yet get a bigger carb. Personally I tried the stock carb...no thanks.

To cool it down cheap, there's not many options,

The hpi cdi would do wonders, but it's $300.

A water cooled head would be great, but you have to find one.

Most people run a Wc kit instead of just the head. But that's$$$.

Check out my cheap ass fan cooling mod. It works wonders but it won't help you if you have airleaks or are under jetted...

Start with the basics. You need to read up on tuning.

Read everything you can find in the wiki and in threads about carb jetting, points timing, larger carbs, reeds, air leaks, crank seals, etc....

30 year old rubber does not not seal effectively.

They can create high rpm air leaks causing lean bogging and cutting out and seizing. I speak from experience. Air leaks are motor killers. They cause lean running, thus HOT!

You need to get a clutch puller and a puller to remove the timing cam under the flywheel (2 or 3 jaw puller works) to get to the seals.

If you don't change them you're being a dummy.

As for performance, a larger carb jetted correctly will give you substantially better performance, but you'll eat more gas.

Lol alright. Well I already have a clutch puller. I guess I need a second jaw puller as well? And i guess while I'm at it should I change any other seals? Or even replace the crank as well? I have read that an 88 jet with the same mods on other hobbits is about right possibly even slightly rich. I havnt done a plug chop but just by looking at the plug it looks almost black not grey which would indicate its running lean. I get the whole running lean at high rpm aspect of the seals tho.

How much is the jaw puller and seals?

Also I know if I'm going to take everything apart to get to the seals I might as well replace the cdi unit as well... And others say after you install the new cdi you often have to down jet.

What size jet do you ru in your setup?

Seals are cheap and easy to install but I'm doughting just seals will fix the whole problem.

Hobbits are natorious for running hot even with good seals.

I'm assuming you installed a cdi? Did it make a big difference?

I don't have tons of money to drop either. So after I replace the $5 seals what's next becase I know that won't be enough to drastcaly drop the temp for prolonged riding.

How did you convert it to a points bike?

And its not shutting down... I mean I can keep going i just didnt want to damage it. It just slows from like 45 to like 35 when it gets really hot. Sounds like I do need to replace the seals tho.

If my top speed is around 45 down a slight hill and I install that dellorto carb and intake kit on treats what kind of top speed increase should I expect? And won't that carb kit get rid of my jetting problem?

I have also seen some people install the dellorto with a large canister airfilter that sticks out the side. Is that a better option than the kit which is pretty much fits in the subframe?

Stock head with polini kit

What plug are you running? I dropped about 75 degrees switching from my winter plug to my summer plug. The bigger the electrode the more heat in the cylinder. An 88 jet is too small, I ran an 88 in my stocko shocko kit. You should be in the 90's with 70cc. An 88 jet with leaky crank seals will make you run hot. Replace the crank seals for sure. They can be done without splitting the case. Go to menards and get one of those laser temp gauges for about $40. As far as a bigger Carb, just bore out your stock Carb. I went up to 14mm on mine and it runs fine. (Just be careful if you go that big not to break out the sides) maybe start with a 1/2" drill first which is just under 13mm.

the cheapest thing you can do is try narrowing the point gap a little bit. i think stock is .016 if i recall, try .014.

the next most expensive thing is going to a bigger jet, the last time i tuned one of these I ended up with a 92 jet. if you have pulled the snorkel thing out, you might want to put that back in, the stock carb seems to prefer it.

tuning your variator also may help, you might be turning goofy high rpm's, in which case you are more likely to overheat. If you dont know what you are doing, you might be better off with a stock or notched variator to take one variable out of the equation.

tuning isn't a 'buy things and throw them at your bike till it works' proposition... its something with a methodology that you go through step by step. if you dont know what you're doing its best to eliminate as many variables as you can and work through things that could be causing the problem 1 by 1. More likely than not, your shaft seals are fine, you probably have an intake air leak, exhaust air leak, wrong timing, wrong jet, or something else free and simple.

i lived in ohio. ngk 6's all year around, gap of .014. what changed was my jetting. then again... i never had significant variance in temps and never had temperature problems.

you pick a plug that works with you mix and then you adjust jetting. you dont adjust temperature with a plug. the plug is either going to work, foul or preignite and make you seize.

"Causes of Overheating:

Spark plug heat range too hot

Insufficient tightening torque and/or no gasket

Over-advanced ignition timing

Fuel octane rating too low (knock is present)

Excessively lean air-fuel mixture

Excessive combustion chamber deposits

Continuous driving under excessively heavy load

Insufficient engine cooling or lubrication

The most serious result of selecting a heat range that is too hot is overheating. Overheating will cause the electrodes to wear quickly and can lead to pre-ignition. Pre-ignition occurs when the air-fuel mixture is ignited by a hot object/area in the combustion chamber before the timed spark event occurs. When the spark plug firing end (tip) temperature exceeds 800°C, pre-ignition originating from the overheated insulator ceramic can occur. Pre-ignition will dramatically raise the cylinder temperature and pressure and can cause serious and expensive engine damage. When inspecting a spark plug that has experienced overheating or pre-ignition, blistering on the ceramic insulator and/or melted electrodes can sometimes be found. " (edited)

^ exactly.