Another reg/rectifier problem, help pls

[Harry the Spider]

Hi, have recently bought a 98 firestorm as a second bike and went to start it the other day, flat battery, battery was brand new in February, recharged it tested circuit, reg/rectifier blown, purchased a new one off e(scam)bay and replaced it. Plug was burned out on loom, bought new plug and replaced too. Battery was showing 12.6v with ignition off, 13.2v at idle and about 14.2 at 5000 rpm, increasing and decreasing with revs as expected. Started it last night, took for a ride, bike was running crap, popping and farting, tool reg/ rectifier off, checked wiring and the red wire had pulled out from plug, i pushed back in, bike runs fine but i checked battery, 13v ignition off, 14.4v constant when running from idle, voltage does not increase or decrease with revs, I'm assuming new reg/rectifier is knackered and will this constant 14.4 charge fry my battery and electrics? I've seen people recommending CBR125r and R1 reg/rectifiers as replacement units, but why not just replace VTR1000 units? Are they renowned for blowing? Any help/ advice will be greatly appreciated, thanks, Lee

[Wicky]

Don't replace the unfinned one like for like as its renown for overheating and cooking itself and the battery + other vital electrical subcomponents. Post 2001 Honda upgraded the R/R with an improved finned version on all their models. So using one from a CBR125 is cheaper as breakers don't perceive it as worth much but it is the improved version all the same.

CBR125 R/R £10 > http://www.gumtree.com/p/cars-vans-moto ... 1015061127



Search for more info on Mosfets - as this will give much more long term reliability.

From the manual

VTR1000F (Superhawk) Firestorm Service Manual PDF > http://www.vtr1000.org/phpBB3/viewtopic ... 31&t=18025

Regulator/rectifier regulated voltage - 13.5-15.5 V/5,000 min-1 (rpm)

The Workshop Knowledgebase > http://www.vtr1000.org/phpBB3/viewforum.php?f=31

[VTRDark]

Plug was burned out on loom

Sounds like the old one was overcharging, so check the battery is still OK and holds a charge. When a R/R overcharges it normally burns out cells in the battery. 14.4 is about the maximum they should go, as long as it does not get up the the 15 mark, you should be OK. Does it drop at all when you switch lights and stuff on, it should drop a bit. Also make sure you have a good earth.

(:-})

[tony.mon]

Agreed, 14.4 is fine, I have a voltmeter display on mine and after starting the bike it charges at 14.4 for a while, then drops to 13.4- 13.8 after three or four minutes. It's just replacing what you took out of the battery firing it up.

The burnt out plug is often a loose connection rather than a failed RR, because there's quite a lot of current produced by the alternator, if there's any loose connection on the alternator to RR wiring it leads to arcing across the gap; this makes a lot of heat, melting the connector plastic and leaving burnt marks on the connectors..

[Harry the Spider]

Thanks for your help guys, I have purchased the cbr125r reg/rectifier off gumtree, nice shout mate, should get it Tuesday or Wednesday, but ain't been able to look at bike over weekend as its pissing down and ain't got a garage , but if this one blows too I have found this http://vtr1000f.wickidnet.com/ thanks again

[Harry the Spider]

Managed to get to test bike today, soldered all wire ends, made sure everything good, good earth, good connection on plug etc, readings are as follows

Ignition off - 12.42v
Ignition on - 12.33v
1200 rpm lights off - 14.78v
1200 rpm lights on 14.63v
5000 rpm same readings as 1200 rpm

Voltage does not increase or decrease with revs, which it did do for 2 days, I'm sure it's knackered, bought new off ebay, it is a finned one, but prob chinese shite as it only cost £30, dealer says they've never had one break before, but will replace if it is definitely at fault, but I should have the CBR 125r reg/rectifier on Tuesday, I'll plug that in and see what happens. Thanks again

[darkember]

Wemoto sell the genuine article for £60. As mentioned before the 125 version will do the same job.