Dr Big

Full Version: Carb refurb.
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Hi all, decided to do a general checkup and carb refurb on my DR 750, last year (before I put it away), occasionally it would suffer carb leakage, so this week I fitted new float needles, new brass seats, new O rings all round and new gaskets using a Japanese made TourmaX kit.
The thing I found was the springs in the new needles were much stronger than the old, which leads me to think that the floats were lifting too much, causing the leaks.
I also had the fuel tanks off to check the plugs and tappets and fit a new throttle cable then noticed when the connector below the tanks was open, it was leaking as the seal in the socket was loose, so I ordered a new socket from Robinsons, which arrived this morning...very reasonable at £16.94 inc post.
So a 10mile run to the MOT station and it passed, so I'll tax it on Monday...and give it a good run...lovely old bike.

Make that Tuesday...
Brill Dave. 

Any link for the kit? Was it expensive? 

Can you explain to me again the effect of a softer spring in the needle re leaks please? 

I've noticed my lhs carb can do any ocassional widdle out the overflow. A slight tap of whatever will solve it. Happens one in twenty times on the side stand. The stands mount is slightly bent which doesn't help matters. 

You've mentioned before doing this work without carb removal. Do you pull the header?

Btw if you're ever selling this bike I'd love first refusalSmile
Hi Colum..#1...the kit was listed on ebay as a DR800 carb repair kit, quite reasonable at £16:90 for two carbs.
#2...I assume that if the floatation ability of the floats is greater than the spring pressure in the needle, then the floats will raise higher than they should, causing a rich mixture and leaks....only a theory mind.
#3...No, but it's a tight fit, especially with having the later drain plugs on the float bowls. First I remove the LH bowl & float assy, which gives better access to the RH bowl screws. When I rebuilt the bike years ago, I used allen cap screws, which are much easier to remove than the std cross head screws.
I'll give it a good run on Tuesday and report back.
Well, took the bike out for a run last week and glad to report, that it runs well...in fact, very well.
Good to hear that Dave, doing the carbs on a Big is a right pain in the bum.
Funnily enough, I was out yesterday and my Big conked out.
I`d just gone onto reserve and it just spluttered and died and wouldn`t restart.
Not much fun when you are on an unlit tiny country lane and it`s getting dark.
I spotted fuel dripping out of the airbox breather so I guessed that a float had stuck open.
After turning off the fuel and spinning it over for ages, the float must have returned to its correct position as the old girl fired up and I got home without incident.
As I had no idea where I was it would`t have been much help calling out the breakdown
The joys of owning a Big .......