Member Contributer CBVFRbikeboy Posted February 23, 2013 Member Contributer Share Posted February 23, 2013 So I pick up an '84 VF750F that was close, and the right price. The PO says it ran, but had a low speed misfire. I can work with that I reckon. She's a little rough around the edges, but that's what a project is right? While I wait for a new battery I decided to open the carbs to see what condition they were in. Obligatory before shot: Anyway, when I opened them up, they were bone dry, and only had a slight film of filtered rust. Pulled the jets and they were fine too, so I pulled the rack apart and gave them a going over with the glass-bead blaster after taping them all up. I'll replace the caps later. and after, fitted up again: I gotta say I was expecting all sorts of hassle removing and installing these, but in the end it was all quite painless. I've had more trouble with the CB900 and the airbox issue. I did have to remove them once to re-fit the throttle cables tho. Won't make that mistake again. So I turn my attention to the fuel pump. I hooked up a temporary petrol supply and found the connector to the pump and ran some wires to the battery. Got my squirt of fuel, so I figure the pump is OK. Reconnect the connector, and turn on the ignition. Now the battery that came with the bike has just about had it, but I thought it would be ok to do some circuit tests. The pump worked when wired directly, so I think there's enough juice. It won't crank the motor, but I'm not ready for that yet anyway. I was expecting the pump to kick in and fill the carbs, but nothing happened, so I'm wondering what triggers the fuel pump? I think A in this pic is the pump relay? and is B the main relay? They both seem to be getting power with ignition. In fact all the static electrics are working (lights/indicators etc). While I'm in question-asking mode, what is the "tail light" idiot light indicating? It lights initially, the fades out after a second or 2. cheers ian Link to comment Share on other sites More sharing options...
nedhills Posted February 23, 2013 Share Posted February 23, 2013 love the comstars! the A relay is for the signals and the tail light going on at the start is normal. looking forward to the re-build. good luck, Brenden Link to comment Share on other sites More sharing options...
rainman6 Posted February 23, 2013 Share Posted February 23, 2013 That already looks very tidy Bike Boy! Looking forward to your restore - the way you made the crabs shine is a promising start! How many Km on her? Link to comment Share on other sites More sharing options...
thx113 Posted February 23, 2013 Share Posted February 23, 2013 I think you will have problems with your brakes Ian, they do not look to be setup for maximum efficiency.. Are you just getting this running or are you going to do a resto? Has it got the original collector box on? Looks like a set of pipeline mufflers bit I can't see what they connect to. Also remember DSS does a pretty good deal on caliper rebuild kits but replacement brake pistons are a bit cheaper over here (if you can get a 20% discount from the local dealer). Link to comment Share on other sites More sharing options...
Guest Posted February 23, 2013 Share Posted February 23, 2013 That does look tidy Ian, congratulations on that find. Have you had it running yet? I would be so impatient to hear it running! Good luck with the resto/rebuild/tidy up. It really doesn't look like it needs much done to have it on the road again. Regards, Tony Link to comment Share on other sites More sharing options...
Member Contributer Kel Posted February 23, 2013 Member Contributer Share Posted February 23, 2013 Looks very promising. You're building quite the old school stable. I'm watching this one. Link to comment Share on other sites More sharing options...
Member Contributer CBVFRbikeboy Posted February 23, 2013 Author Member Contributer Share Posted February 23, 2013 thanks guys. Yeah, all the calipers are seized. I've got a pair of 1100 units on the front to just wheel her around the shed, so I'll have to rebuild the originals. The pics tend to flatter her I'm afraid. She's a bit worn out. Only 36K kms on the dial but. The plan is to restore her. No collector box Jeff, just the 4-2 headers pipes. Yeah Kel, I'm stuck in the 80's. You should hear my iPod ;-) I'm still not sure what the tail light warning light is supposed to indicate? And when does the fuel pump activate? Should it go on with ignition? cheers guys ian Link to comment Share on other sites More sharing options...
kman Posted February 23, 2013 Share Posted February 23, 2013 The fuel pump will turn on with a signal from either oil presure or from the ignition module.This will turn on the relay and energize the fuel pump. Just turning on the key will not do it. Don't forget to pull the cam covers and inspect the the cams for worn lobes. This could be contributing to the low end misfire.(hopefully not!) Link to comment Share on other sites More sharing options...
Member Contributer Mohawk Posted February 23, 2013 Member Contributer Share Posted February 23, 2013 Ian the tail light indicator is to inform you if your tail light has failed. It lights at power on like the oil pressure light & does a continuity test, thus lighting the dash warning light, to prove the dash light works. Then it goes out. If the tail light fails whilst riding, the dash light will come on to warn you ! Great at night to stop you getting rammed. Most bikes has dual tail/stop lights now so no need for a single bulb check system ! Link to comment Share on other sites More sharing options...
Member Contributer Kel Posted February 23, 2013 Member Contributer Share Posted February 23, 2013 thanks guys. Yeah, all the calipers are seized. I've got a pair of 1100 units on the front to just wheel her around the shed, so I'll have to rebuild the originals. The pics tend to flatter her I'm afraid. She's a bit worn out. Only 36K kms on the dial but. The plan is to restore her. No collector box Jeff, just the 4-2 headers pipes. Yeah Kel, I'm stuck in the 80's. You should hear my iPod ;-) I'm still not sure what the tail light warning light is supposed to indicate? And when does the fuel pump activate? Should it go on with ignition? cheers guys ian HA...I here ya, my 8yo son hums more Devo, Kraftwerk, and INXS than anything else. Link to comment Share on other sites More sharing options...
Member Contributer CBVFRbikeboy Posted February 25, 2013 Author Member Contributer Share Posted February 25, 2013 I'm thinking I should install an in-line fuel filter to this thing. Is there anything I need to consider when fitting one on a bike with a fuel pump? cheers ian Link to comment Share on other sites More sharing options...
ADHD Posted February 25, 2013 Share Posted February 25, 2013 Most bikes fuel taps have a built in filter, but you should install a good quality in-line filter able to stop particles down to 0.0015" or 40 microns. I like to use a glass housing ones you can take apart for cleaning, when you see they are dirty. You can used a cheap universal ones but make sure you change them often - at least once every two years, depends on how clean is the fuel in your area and the condition of your fuel tank. I usually put two filters on a bikes with fuel pump. One before, and one after the pump (it might sound a little bit to extreme, but this is something I was taught in college by my teacher with 40 years of experience in bike racing). I do find some dirt in the second one quite often. If you want to use just one, fit it before fuel pump. Link to comment Share on other sites More sharing options...
Member Contributer CBVFRbikeboy Posted February 25, 2013 Author Member Contributer Share Posted February 25, 2013 Thanks ADHD. I wasn't sure if the inline filters would coupe with the pressure from a fuel pump, because all the others I have are just gravity-fed. Good idea on the before and after too. I haven't been able to open my tank yet, but it sounds like there's some flaking rust swishing around. Pulled the fuel sender, and it had a bit of rust on the arm. I'll clean it out eventually, but I'll still fit the filters. cheers ian Link to comment Share on other sites More sharing options...
Member Contributer YoshiHNS Posted February 25, 2013 Member Contributer Share Posted February 25, 2013 An in-line filter will be fine on a carbed bike. The pump isn't putting much pressure out to worry about anything. Link to comment Share on other sites More sharing options...
Veefer800Canuck Posted February 25, 2013 Share Posted February 25, 2013 the pumps on the old VF's are extremely low pressure. put the filter on the discharge side of the pump, before the carbs. The bike should have always had one, did someone remove it during it's life?? Link to comment Share on other sites More sharing options...
hoganth Posted February 26, 2013 Share Posted February 26, 2013 OEM fuel filter should have been attached to your pump at the fuel pump mounting plate near the bottom. Unless it's been removed! Link to comment Share on other sites More sharing options...
Member Contributer CBVFRbikeboy Posted February 26, 2013 Author Member Contributer Share Posted February 26, 2013 the pumps on the old VF's are extremely low pressure. put the filter on the discharge side of the pump, before the carbs. The bike should have always had one, did someone remove it during it's life?? OEM fuel filter should have been attached to your pump at the fuel pump mounting plate near the bottom. Unless it's been removed! there may well be one fitted at the pump, I just haven't got down that far yet. Good info thanks guys ian Link to comment Share on other sites More sharing options...
Veefer800Canuck Posted February 26, 2013 Share Posted February 26, 2013 the pumps on the old VF's are extremely low pressure. put the filter on the discharge side of the pump, before the carbs. The bike should have always had one, did someone remove it during it's life?? >OEM fuel filter should have been attached to your pump at the fuel pump mounting plate near the bottom. Unless it's been removed! there may well be one fitted at the pump, I just haven't got down that far yet. Good info thanks guys ian IIRC, it may be fitted with a protective cover, it's been a million years since I owned that bike....... Link to comment Share on other sites More sharing options...
hoganth Posted February 26, 2013 Share Posted February 26, 2013 Yes, it is at the "Pump" very short hose shaped like a horse shoe. I would put up a picture for you but don't have one handy. Look at a online parts locator and you will see where it is. Good Luck! Link to comment Share on other sites More sharing options...
Member Contributer CBVFRbikeboy Posted March 5, 2013 Author Member Contributer Share Posted March 5, 2013 Lesson #1. Test any replacement parts before refurbishing them: I used a spare pair of cb1100 calipers on the front while I attack the VF's, so I just assumed the rear would work as well. Not so. There is a clearance issue with the mounting points and they don't bolt up. On another note, I got her running :-) I have an audio file on my phone, just need to figure out how to download it :-( So having established it as a runner, its time to start dismantling. An hour or 2 later and you get to this stage: and of course every project motor needs a stand while you work on it: so onwards and upwards ;-) cheers ian Link to comment Share on other sites More sharing options...
Veefer800Canuck Posted March 8, 2013 Share Posted March 8, 2013 nice. I say again, love those wheels. we didnt get them here. i wish i had one of these, this was a stock euro colour: Link to comment Share on other sites More sharing options...
Member Contributer CBVFRbikeboy Posted March 12, 2013 Author Member Contributer Share Posted March 12, 2013 So I figure not everything needs to be powdercoated. These headlight frames are a good candidate for the gloss black rattle can I reckon. They're not exposed to the elements and I doubt they'd even get wet in the rain? Link to comment Share on other sites More sharing options...
Member Contributer CBVFRbikeboy Posted March 20, 2013 Author Member Contributer Share Posted March 20, 2013 Gee I really like these gold boomerangs but bugger me the hubs are a pain to clean and repaint! Link to comment Share on other sites More sharing options...
thx113 Posted March 20, 2013 Share Posted March 20, 2013 Is that new? Link to comment Share on other sites More sharing options...
Member Contributer CBVFRbikeboy Posted March 20, 2013 Author Member Contributer Share Posted March 20, 2013 Is that new? na mate, I wish. I don't have a good 'before' pic, but the hub and disks were pretty manky. Fortunately the anodised parts came up pretty well with some autosol. Just a couple of the usual war wounds. Came up pretty well overall. Doing the rear now, and for the first time ever the 'double-nut' technique work for me to remove the drive sprocket studs Only needed to penetrine one of them. They're sitting in the electorplating bath now getting a new coat of zinc The rear disk has more rust on it than the front, but it seems to come off with one of those synthetic paint remover disks. I'll get some before and afters if I remember cheers ian Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.