Cafe Build Project Progress

[EJ8TrapKing]

Hi all I'm very new to building motorcycles and I am very inspired to finish this already started cafe racer build. I will try to keep one main thread to keep all new information together, and show the progress of my work. With patience and the help of the community I absolutely feel like I can finish up this project if I put my mind to it. Any feedback are welcome.

Here is what she looks like.

 

[EJ8TrapKing]

Just cleaned the carbs and now its running, but its too raw.It backfires and needs a tune up and eventually I will need to know what has to be serviced.

 

[bcware]

How are you going to address the clearance on the tail section? Unless you set your rear shocks to maximum stiffness that is definitely going to bottom out and hit the tire.

 

[jmd_forest]

Backfiring is often due to running lean because of an air leak in the intake. Also could be from running without the original air boxes causing a lean condition. However, I would look at the intake manifolds (rubber mounts between the carb and engine) for cracks, as well as the carb diaphrams and throttle shaft seals. Another option is that the carbs are not as clean as youn think they are. There are many tiny orifices and jets that need to be near surgical clean. A third option on the back firing could be ignition timing.

Best of luck with your build. It looks like you are off to a nice start.

 

[bcware]

4th option; he's running a 2-1 exhaust with pretty much no muffler so he's running lean. Increase the jet sizes.

 

[EJ8TrapKing]

I can see it now

 

[EJ8TrapKing]

How are you going to address the clearance on the tail section? Unless you set your rear shocks to maximum stiffness that is definitely going to bottom out and hit the tire.

Oh those picture are before I got the bike and the previous owner half-assed the tail, so I'm going to make my own seat. I like the style but needs work, so i'm gonna use the old tail as a mold to make the new one. Any ideas on how to make a seat?

 

[EJ8TrapKing]

4th option; he's running a 2-1 exhaust with pretty much no muffler so he's running lean. Increase the jet sizes.

How do I increase jet size?

 

[EJ8TrapKing]

Backfiring is often due to running lean because of an air leak in the intake. Also could be from running without the original air boxes causing a lean condition. However, I would look at the intake manifolds (rubber mounts between the carb and engine) for cracks, as well as the carb diaphrams and throttle shaft seals. Another option is that the carbs are not as clean as youn think they are. There are many tiny orifices and jets that need to be near surgical clean. A third option on the back firing could be ignition timing.

Best of luck with your build. It looks like you are off to a nice start.

I understand that the carb needs to be super clean and I really would like to sonar blast it, but I got quoted at 200 bucks. So thats out of the question. Is there a home remedy to super clean the carbs?

 

[Philodoxo]

Hi EJ8TrapKing

How did You make knee-dents in Your tank ? Or is it not a standard XS400 D tank ?

 

[drewpy]

I understand that the carb needs to be super clean and I really would like to sonar blast it, but I got quoted at 200 bucks. So thats out of the question. Is there a home remedy to super clean the carbs?

200 bucks for sonic cleaning? buy a jewellery one 2nd hand and do it yourself

 

[phate]

If you have a Harbor Freight near you can get a good one for about $70 and then return. A lot of people (including me) have had success with the carb cleaner/compressed air combo granted it took me about 5 cleanings. About the jetting there is a lot of info if you search it (I think someone just a few days ago asked the same exact question) but to be brief it is basically the act of increasing/decreasing (in your case increasing because of your current leanness) the size of the jets located inside the bowl of the carbs. This will either increase fuel flow richening the mixture or decrease fuel flow leaning the mixture while you try to find an equilibrium between the 2 states. These jets can be purchased on mikesxs.net. About the knee dent I remember seeing a thread in the tech section... ahhh hear it is http://www.xs400.com/forum/showthread.php?t=4694
Anyways the bike looks great I really like that color

 

[LuckyEight]

Hi EJ8TrapKing

How did You make knee-dents in Your tank ? Or is it not a standard XS400 D tank ?

It looks like a tank from XS750

 

[EJ8TrapKing]

yes it is an xs750 tank