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Tune up specs for 1973 XL100 and 1979 XR80

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Does anyone have the tune up specs for:

1973 XL100

1979 XR80

Valve intake and exhaust

Point gap (points, yikes!)

Spark plug and gap

etc.

I picked up a couple of project bikes.

Step 1 is tune up.

Sources for points and condenser appreciated too.

Thank you in advance,

Kevin

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The following is from page IX of the Clymer book, Honda 100-350cc OHC singles 1969-1982.

100 and 125 Valve clearance. Intake 0.002 Exhaust 0.002

Spark plug type, 100-125 and 175 (through 1976) NGK D8ES-L gap 0.024-0.028

Idle RPM CB100-CL100-SL100-XL100 --- 1200 +-100rpm

Contact breaker point gap 0.012-0.016

Sorry, can't help you on the 80.

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XR80:

Valves: 0.05mm (.002 in)

Compression: 170 psi

Plug: ngk c7hs

Plug gap: .6 -.7mm

Points throw them away and get a CDI!!!!!!!!

Ok, Points gap .3 -.4mm (0.012 - 0.16in)

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Thanks for the info.

Is is possible to upgrade an older bike to CDI? If I can do that for the 79 XR80 or 73 XL100, that would be great.

Also, were is a good onlines parts phish?

I need to see if the clutch basket on the XL100 can be replaced by a newer XR100 basket.

Honda reuses parts over and over.

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Socalxr can help you with the CDI conversion, as I don't know about the smaller bikes. The only small bike I have with points is a 1978 Z50, and it runs good enough for what I need it for. I did convert a 1975 XL350 over to CDI. Simple, but costly if you use new parts. If I remember right, mine was about $300 all used parts. The main cost for the XL350 conversion was the stator. It has to get rewound from 30 volts to 90 volts. I know that sounds like high voltage, but I've never seen a bike start so easy, vintage or modern. It will start with-in half a stroke of the kick starter, first time, every time.

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I just do XR80/100's. It's pratically a direct bolt-on. I don't have any experience with any other bike.

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Everything bolts on. you need to grind a little piece that stick up under the stator and make a bracket to hold the Black box and coil. It will bolt under the tank. The cost is about $100-$175 off ebay. You could get a step key, but it's not neccessary.

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