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About roffster

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  • Birthday 05/28/1964

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  • Current Bike(s)
    Yamaha DT 250 MX, Suzuki GN125

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  • Interests
    Motorbikes, Mountain biking, Rugby,
  1. thanks blackhat, good advice. I will hopefully get round to it this weekend. Do you have any pictures of yours after the mod?
  2. So it's been a bit quiet on the DT250MX front the last two weeks. It was a busy weekend mountain biking in Wales last weekend which put paid to my planned work on the bike (I can't wait to get an engine to get me up the hills. Fat Old Git power wears a bit thin after about 10 mins) Anyway the bike immediately ran into delays because of the Clutch centre boss which is what is stopping the engine going back together for a trial start up. Nothing on ebay, there was one on ebay USA but it turned out he wouldn't ship to UK even though the listing said differently. CMSNL had it listed and I ordered it with the one odd clutch spring screw and washer I needed, over 70 Euros with delivery but I didn't want to hang around for ever. As luck would have it they then rang to say they didn't have any left and couldn't get one, so it was back to the hunt. I tracked a NOS one down in Canada from www.MyOldYamaha.com and what is more it was on sale at only $39! I have to say Ken Broden from the site has been brilliant in sorting me out with the part, he even threw in the final clutch spring screw and washer he had for me. All in with shipping and tax was $69 (£43) I think that is pretty good considering a good chunk of that is the shipping. It should arrive in the next week and then it should allow me to put the clutch in and get the case back together and give her a try (god I hope the clutch boss is the right one). This weekend I'm going to drill out the oil inlet on the Carb body to allow me to fit the nozzle that Paul so kindly gave me. I'll post some pictures of the operation after the weekend.
  3. I just checked by spraying carb cleaner through and a good strong jet comes out of the hole, it is fine but does this mean the pump will spray the oil through the small hole under pressure? It is definitely coming out of the hole I have a line pointing at the hole in the photos. in the second one you can just see it in the shadow. It is small though isn't it?
  4. Hmmmmm. pgm have come back and the brass spigot on their elbow is 3.3mm. I'll measure the hole again but I am pretty sure it is narrower than that. Looks like I'm drilling.
  5. Yes I was a bit worried about leaving any debris in the hole. I have emailed pgm so i'll see what they come back with, I'd imagine the minimum is only because of the free postage but I don't mind paying that. If push comes to shove I could buy a few if it fits and then they be sold as compatible with DT250 carbs. I'll see what theirs measures up as and then make a decision on the drilling, I would definitely use a pillar drill. The hole it comes out of in the intake base is tiny, not much bigger than a pin hole, it seems hard to imagine enough oil getting through it. Thanks guys.
  6. YPVSTONE and oldgitonabike, I was just thinking I could drill the hole out to 4mm. There is plenty of meat on the casting, what are your thoughts? There doesn't seen to be a part specifically listed for it anywhere. Once in it's in I suppose, am I being stupid or is that a viable idea do you think?
  7. Well, I sprayed carb cleaner into the hole and sure enough it comes out of a tiny hole I hadn't even spotted on the base of the intake just as YPVS TONE had said, so this is the right hole! Then delivered by armoured carrier, the spigot that oldgitonabike had very kindly removed from a spare 175 carb arrived this morning...........................Too big! What were Mikuni thinking? why isn't a common hole on many of their carbs not the same size?? Paul your spigot measures 4mm in diameter and the hole looks to be 2.5mm. Thanks anyway but it is back to the drawing board for me. If you pm me your address details I will send your spigot back for safe keeping. I'll have to send a message to pgmyyamaha and see if the RD measures the same size and then persuade them to sell me one if it is. I ordered the clutch centre boss yesterday, so if that arrives soon then I think I'll be trying to start her up with pre-mix. Not the end of the world, but dissapointing. I guess I'd better get used to dissapointment as I'm sure that this won't be the only setback I experience getting the old girl back on the road.
  8. Oldgitonabike, I would like to take you up on that offer of the spigot if you don't mind. It seems Tony has unearthed proof not to be argued with. You'll let me send you something to cover it and the postage please?
  9. Tony they are the best pictures I've seen so far and it seems to clear as day now. So my photo journalist bit above is useless. Thanks for your help. Much appreciated.
  10. Anyway, I whipped off the carb and took a picture from each side with some labels to aid the discussions. I looked very hard and scrubbed a bit and can just make out a number on the carb body it is 1R7 00 so it matches with the frame and engine type number. The float arms are different to the diagram in the MX supplement of the manual but the rest of it looks the same, so perhaps the float chamber was kitted out from the spares box on a friday afternoon in Mikuni?? http://i1121.photobucket.com/albums/l503/roffster/Yamaha%20DT%20250%20MX/carbengineside.jpg In the photos I've used the same letters for the parts even if they appear more than once. In this one 'A' is what we think is a breather and the carb diagram in the manual would tend to agree. When you blow through it air comes out of the fuel pipe and somewhere else that I wasn't able to identify but there is obviously an internal airway linking several things. This would seem to back up the breather theory as it does not go straight into the venturi. From the front of the carb you can see 'B' and 'G' are duplicates but 'G' is blanked at the surface and 'B' goes in but does not seem to go straight into the venturi. I couldn't really get at to blow into it but it doesn't seem to allow air through, so maybe this is blanked inside because on other variations of the same basic carb this is where the oil feed is (RD250). The inside and outside of 'B' are the same sort of dirty so it doesn't look like there has been a oil feed pushed in there. 'H' is where the number 1R7 00 is faintly stamped. Next up is the carb from the clutch cover side. http://i1121.photobucket.com/albums/l503/roffster/Yamaha%20DT%20250%20MX/Carbclutchside.jpg 'A' seems to connect in some way to the passage you can see going left to right including the choke mechanism. Inside a small passage starts before the slide and joins the inlet just after the slide (choke?) 'B' you can see the uniform dirt and colouration. In the next picture you can see the start of the channel I mention above which might be the choke circuit (sorry I am not a mechanical whiz, this is my project to learn more. A nice simple two stroke ) http://i1121.photobucket.com/albums/l503/roffster/Yamaha%20DT%20250%20MX/carbairfilterside.jpg When I blew into 'A' I don't think any air came out of 'D' or 'E' Finally the Carb from gear lever side http://i1121.photobucket.com/albums/l503/roffster/Yamaha%20DT%20250%20MX/Carbgearchangeside.jpg 'G' opposite 'B' and as mentioned blanked at the surface unlike 'B' 'F' is the one breather/overflow I can identify positively. There you go folks, does the confirmation of the number on the carb help any. All answers and suggestions are gratefully received.
  11. That is very nice indeed! Did you do it all from scratch? I was going to use a brass brush, but after your words of caution I think I'll take it a bit slower. Did you get one of those smallish ultrasonic baths used mainly for jewellery? I was looking at them on fleabay and they are a fairly decent price. Here is a picture of mine from the weekend. 1st time in daylight for about 11 years, I've taken the tank and saddle off to make it easier to work on. But I think she is basically sound apart from the clutch centre boss and clutch plates I've got to replace. http://i1121.photobucket.com/albums/l503/roffster/Yamaha%20DT%20250%20MX/bike.jpg
  12. You're a gentleman! And a star, I'll whip it off tonight and get some piccies and have a look at that hole. Having seen your beautifully clean and shiny 175 carb you've also shamed me into getting the new dremel I bought yesterday out to have a go with the wire brush on the carb body Damn peer pressure! Is that how you did yours? I'd love to see some pictures of your bike if you have any posted anywhere/
  13. Tony posted a link to a retailer that sells the RD oil injection elbow which is a push fit. Unfortunately they have a minimum order of £20 so I couldn't buy it to try it as it is only £5. I don't have an RD with one on. I'll look at it again and if it is the right place I'm sure there'll be a way to mackle it, or I'll have to ring and beg pgmyyamaha to sell me one despite their minimum order limit. Or I guess I could just plug the hole and run premix, seems a shame though.
  14. Thanks for posting the photo, I am also leaning towards that conclusion. Is that Spigot a push fit item and do you think the RD spigot would fit? They both use a Mikuni VM28 carb I think (or is that too simplistic?) The frame and engine numbers begin 1R7 which i think denotes them as being from MX models. The more I look at my photo having seen your 175 carb the more it seems to make sense. That is the only hole on the carb around that area that isn't obviously blanked off. I can't wait to get it off again and have another look. I think I'll be in the garage with a headlamp tonight. I looked for the number on that little square moulding on the carb body, my eyes are not what they were and it was a bit dim but I couldn't see anything. I'll look again tonight.
  15. No the bike was running on the autolube system. Of course when I took the clutch cover off over 10 yrs ago I though I would remember everything!!! Schoolboy error! But I did leave the oil pump connected and in situ on the clutch cover so the only thing that was disconnected to let me move it out of the way was the oil feed to somewhere on the carburettor. I will take it off again and check both the nipple that might be a breather and the hole that may have a spigot missing and see what goes through to where. Do you have any idea where I might be able to find a carb number hidden? I thought I had a pretty good look when I cleaned the carb last weekend but couldn't see anything.
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