Yamaha (RD350 YPVS or also called the RZ350) CDI problem FIX?\n\nYamaha RZ350's (especially 1983 and 1984 models) have a CDI problem\nthat\ncauses it to fail over time. A used unit from a a newer model don't\nwork\nunless you replace most electrics. I heard of some people fixing this\nproblem by taking the CDI apart and replacing or soldering the\nfault. It's hard to take the CDI apart but I never seen anyone release\nthe\nfix or a schematic of the CDI with test procedures.\n\nDoes anyone have a schematic/circuit details or know how to test, FIX\nthis\nCDI?\n\nAll the info I have listed here I found posted in newsgroups, etc but\ndoes not include repair info. If you change the stator/CDI/coils from a\nnewer model, it will work BUT it would be nice to know how or why the\nCDI\nunits are failing and what (transistor/diode/resistor) needs to be\nresoldered/replaced.\n\nPLEASE post any technical info about this problem.\nI'm interested mainly in the 1983/84 CDI info. New CDI's also have\nproblems but\ndon't have a high failure rate like the 1983/84 models. Someone below\nalso said they fix the problem but never posted the fix and the e-mail\nfrom\n1997 don't work anymore.\n\n-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\n\n\nThis may sound obvious, but did you check the spark after it cut out.\nSupposedly there was a design flaw in the cdi box that caused them to\nfail at a high rate. My bike has a broken box. Have to preheat the box\nor park under the hot sun for it to start. If you have a bad cdi, it's\n$$$ to replace.\n\n-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\n\n[QUOTE]\nYes, once it was the black box. Try to borrow one that you know works\nand try it.[/QUOTE]\n\n\nMy second CDI box quit this summer. BUT I fixed it !!!\nTook a couple of hours to dig through the epoxy and gravel but I\nhave fixed it. I am about to attempt this on another box in a couple\nof weeks. Do not throw away your CDI boxes just yet. Just in case\nI have actually figured out how to fix them and it aint just a fluke.\n\n-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\n\ni assumed that the YPVS and\nignition system would be nearly identical. I could not find any spec\nregarding the CDI unit, in fact the manual stated that Yamaha had not\nreleased details at the date of publication?\n\n-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\n\ntighten a large hose type clamp with a dowel on top mid-point applies\npressure\nto the circuit board in the CDI for it to work again. This is ONLY a\ntemp fix\nso you can find a replacement or fix your old one.\n\nThree CDI types on Yamaha RZ350:\n\n29K-50 for 31K 1983-1984 RZ350\n52Y-50 for 57V/1JF 1985-1986 RZ350\n1UA-50 for 1WT/1UA/3DH1 1987 on ?