I just bought a 1990 mojave for 1100.00 two days ago and it is very hard to start and it burns up spark plugs every day, other than that it is a great 4 wheeler.If this is normal is there a electric start you can put on it and were can you get it.Thanks

 

Sounds like if it hard to start then you probaly check your compression and if it burns up spark plugs then check your carb jets

 

Sounds like you have a VERY lean condition causing both the hard starting and the plug burning. I assume that by "plug burns up" you mean the electrode is burned away. If you continue to ride it with this condition you will do major damage to the engine if it has not already. If the bike sat for a long time with gas in the carb before you bought it the carb is probably plugged with nasty crud and will need a
good cleaning. If not check for any other causes of a lean mixture. Could be sucking air at the intake boot, or the rubber intake pipe behind the filter could be loose(happens easy on Mojaves).
also make sure that the in tank filter screen is not restricted and that plenty of fuel is flowing from the tank to the carb. I let mine sit for a long time and the gas formed crud in the screen in the tank. I removed the fuel shut off valve and took the screen off, then put an inline filter in the hose. Anyway, find and fix the cause of the lean mix before you ride it any more!