SR41carb set up Dr750

Questions regarding the DR750

SR41carb set up Dr750

Postby quiffer » Sat Apr 12, 2014 4:39 pm

Hi does anyone have a comprehensive carb set up diagram and instructions as my manual is to vague.

My manual quotes things that are not even on the parts list ?????


Thanks in advance

Quif
User avatar
quiffer
Regular
Regular
 
Posts: 38
Joined: Fri Jul 12, 2013 2:46 pm

Re: SR41carb set up Dr750

Postby ladder106 » Sat Apr 12, 2014 5:12 pm

Can you be more specific in what you want?

Also include mileage on the bike, overall condition of the machine and what you've already done (or haven't yet done) to the carbs.

The only carb parts not included in the parts listing from Suzuki are the grey plastic slide guides and the O ring at the bottom. This can be sourced from the BMW early Funduro that uses the same carb.
User avatar
ladder106
Site Supporter & all round Good Egg!
Site Supporter & all round Good Egg!
 
Posts: 397
Joined: Sat Aug 27, 2011 6:02 pm
Location: Davis, California, USA

Re: SR41carb set up Dr750

Postby quiffer » Sat Apr 12, 2014 5:51 pm

1989 Dr750 with 15k on the clock. Condition is a lot better than when I got her. Good for another 20 years.

Rebuilt the carbs and cleaned everything possible. Had to fit new diaphragms as one had a hole in it.

Refitted the carbs back to the bike and it will not start. Got a good spark at the plugs and the tappets are ok.

Tried to start the bike and can not get any fuel to cyclinder.

Now removed the carbs and blown everything through with compressor.

Before I re assemble just want to check settings against a manual, my Dr750s service manual lists things in it that when you look at the schematic / parts list are not in the carbs????

The inspection lists

As per the manual
#pilot jet
#main jet
#mainjet air
#pilot jet air
#needle jet air bleeding hole
#float
#needle valve
#starter jet
# gasket
#throttle shaft oil seal
#diapgragm
#pilot outlet and by pass holes
#accelerating nozzle

Unfortunately I am not at work or I would scan the page to show what I have.

Everything I can identify from the manual has been cleaned,blown through and hopefully sorted. As they are pain to get on /off I just want to eliminate any mistakes before I try again.

Any ideas ?????????

Thanks in advance


Quif
User avatar
quiffer
Regular
Regular
 
Posts: 38
Joined: Fri Jul 12, 2013 2:46 pm

Re: SR41carb set up Dr750

Postby ladder106 » Sat Apr 12, 2014 6:55 pm

I thought the air jets on the SR41 carbs were pressed in. If you have removable jets you may have carbs from an SR42 or 43. What size is the pilot jet on your carbs??



If you have removable air jets, you can create a non-start condition if you've transposed the 2 air jets that live in the bellmouth of the carb.

The 0.6 jet should be in the midline of the carb. The 1.3 jet should be in the right side position when looking into the carbs from the rear of the bike.

You're correct, the two air jets are not shown in the carb schematic.

Could that be the problem?
Last edited by ladder106 on Sat Apr 12, 2014 7:04 pm, edited 1 time in total.
User avatar
ladder106
Site Supporter & all round Good Egg!
Site Supporter & all round Good Egg!
 
Posts: 397
Joined: Sat Aug 27, 2011 6:02 pm
Location: Davis, California, USA

Re: SR41carb set up Dr750

Postby ladder106 » Sat Apr 12, 2014 7:02 pm

Also....if fueling is your problem, put the carbs on the bench, put some small clear tubing on the drain ports of the float bowls and bend the tubing into a "U" shape so the end is higher than the float level, then open the drain screws, connect a fuel source to the fuel inlet and make sure you visually check the fuel level in the float bowls.

That way you're certain that you can get fuel to that point in the carbs.

If you don't get fuel with the carbs on and the fuel pump connected, you may have bad diaphragms on the pump. Since you had them on the carbs, it may have happened here also.

You can gravity feel the carbs with the fuel tanks down to about 4 liters. The last 4 liters in the tank must be pumped up to the carbs.

You may have better luck installing and removing the carbs if you remove the mounting bolts from the battery box and air box. You can then slide these to the rear of the bike just a bit....but it's enough to let you get the carbs in without murdering the flexible boots.
User avatar
ladder106
Site Supporter & all round Good Egg!
Site Supporter & all round Good Egg!
 
Posts: 397
Joined: Sat Aug 27, 2011 6:02 pm
Location: Davis, California, USA


Return to DR750

Who is online

Users browsing this forum: Google [Bot] and 1 guest

x