Dr Big

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If anyone can help with this it would be much appreciated! I know the post is long but I've tried to give as much background info as possible.

Two weeks ago I bought an 88 DR750 which was running when viewed and was ridden to my house twice by the seller, a journey of just over 30 miles each time.

Within 10 minutes of buying the bike it emptied it's fuel tanks all over my garage due the hose from the T-Junction to the Fuel Tap having deteriorated.

The following day and 9 litres of fuel later I replaced the hose. Once done I put in just 3 litres of fuel and the bike started up fine and was left to idle for five minutes (unable to ride as not currently insured). I switched it off and rolled it back into the garage. A week later I tried to start the bike and although turning over, it would not catch. I have little mechanical experience so have tried what i can to source the problem. The plugs are getting a spark and using a bit of Holt's Easy Start into the air intake (crude I know) it's obvious that if there is fuel there it will catch. This leads me to believe it's fuel starvation, would this be right?

I rigged up a temp fuel tank direct to the filter but when I did this a leak started from the carbs. I thought this could be from the hose that feeds the carbs but after removing and inspecting the hose it seems unlikely and given how difficult it was to reattach even less likely. The nozzle that connects the two float chambers and that the hose attaches to seemed to rotate 180 degrees? Is it supposed to do this to help fitting or is that not right?

I plan to test the bike tomorrow again using the temporary fuel tank. Hopefully the leak will have stopped but I am not holding out hope that the bike will start.

Any help or input would be appreciated.

Thanks in advance,

maybe the fuel pump is goosed....re leaky carbs give the float bowls a wee tap ..somtimes the floats stick if they sit awhile...

also its the law here that you put up pics of your bike Thumbup
Blow down the fuel cap breathers while cranking....blow like your your on a breathalyser Banghead Does it catch then?
Could be that your fuel lines are not genuine or routed correctly.
Who knows if the previous owner hasn`t been messing with the carbs?
It probably needs one of us to stick their nose in and have a look.
Where did you buy the bike?
Where are you located?
Footman James are best for insurance


Thanks for the help guys.

The bike was found on GumTree and owned by a member of this forum who told me about the forum. I live close to Newcastle which unfortunately means I'm quite far from you BigBob Sad

I tried the bike this morning using the temp fuel tank. When connected the leak from the connector to the carb appears to have gone. I gave the carb floats a few taps and it started up on the second push of the button. Thanks for that Kyle.

It cut out twice when idling but could be because it was cold. Thankfully it started straight back up. I'm going to put the tank back on but could do with further help.

The Fuel lines were connected as per the diagram 4-1 in the manual but wouldn't this cause the left tank (as if sat on the bike) to drain first when the fuel tap is set to "On" and the right tank only to drain when set to "Reserve" causing an unbalanced bike? The diagram at 7-18 of the manual appears to show a different set up?

I will start a thread with some pics and progress on the bike once I get this problem sorted. I'm a bit concerned at the minute I've purchased a bit of a lame duck!

Further help would, again, be appreciated.

There is a quick release connector between the tanks, which means they empty equally.
It might sound drastic, but it really is worth changing all the fuel lines for genuine new ones.
I know it`s expensive, but you won`t have to worry about that side of things any more.
The fuel lines are all over 20 years old and sit very close to a hot exhaust pipe!
This is what happens if you dont


I've come across those pictures when browsing the forum and they do make me shiver!

Big Bob, are there any hoses you can recommend? if so do you have a link / contact number ?
Robinsons for parts. Quote my name for 10% off 01227 454366



Thanks for the link, very useful.

I called Robinson's to order parts but was told that they have been discontinued. Bad times.

I've re assembled the fuel lines using the best quality components I could get hold of, replacing worn fuel line. Can someone please clarify where the connected pipe runs? It is currently running between the carb and air box but this seems perilously close to the exhaust pipe.

Is the heat sleeve enough to keep it from going up in flames?
tonight my BIG died: I run it since 2 weeks and 380km, this evening I did 5 km uphill and pretty fast, arrived in place when idling it died.
looks like I have no spark or no fuel.

can someone help me? I'm damn worried Cry
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