What Jets to order?

[beastsr20]

Hey guys,

Currently just in the process of reboring the stock jug 0.10 over and porting/polishing my engine. Was wondering what size jets I need to order.

It currently has a 310 main jet.
Toomey B1 Exhaust
No airbox lid with unifilter.
Dual stage reeds.

Was gonna order 320, 330, 340. Is there any point ordering a 350? I'm guessing 340/350 would be huge for this engine.

Jets are $15each AUD. And I don't have time to order them from the US, hence why I don't want to order what I wont need.

Thanks heaps

 

[Larry's Shee]

310 with what you had almost suggests an air leak, if it plug chopped/read good. Unless you gave it a wazoo port job (drag) even 340 might be big. Leak test it and start rich and work your way down with plug chop/read.

 

[Wifesblaster]

310 with what you had almost suggests an air leak, if it plug chopped/read good. Unless you gave it a wazoo port job (drag) even 340 might be big. Leak test it and start rich and work your way down with plug chop/read.

Toomey sends a 310 main with their pipe. That's what they recommend. Get a 320 and 330. Plug chop the 330 and go with what the plug shows.

 

[Blaaster]

And if you are pre mixing at 32:1 you may consider one size jet bigger to compensate for the lack of gas in the mix!

 

[beastsr20]

Just got it all back together. Fully ported, head mod (still 135psi comp). I was sceptical on the amount of power it was going to make. FK me what a difference, I'd say around 40% more power, its crazy. I upgraded the reeds aswell to vforce 4s. Not sure if they made all the difference or just the porting/head mod. I bumped up the jetting to 330main.

 

[Blaaster]

How was the plug chop?

 

[gb blaster]

Just got it all back together. Fully ported, head mod (still 135psi comp). I was sceptical on the amount of power it was going to make. FK me what a difference, I'd say around 40% more power, its crazy. I upgraded the reeds aswell to vforce 4s. Not sure if they made all the difference or just the porting/head mod. I bumped up the jetting to 330main.

Porting and head mod is what gains these machines the most power.

Make sure that you plug chop to confirm the jet change!

 

[beastsr20]

You guys are gonna frown upon this. I didn't do one. But I plan too tomorrow. I only took it out for a quick squirt. I figured 330 would be fine as the porter told me to go up only 1 size but I went 2.

 

[Blaaster]

So then, did you do a leak test, the heat cycles, re tension and run at no more than 3/4 for a tank or two before you fanged it?

 

[beastsr20]

What I did do is,
5 heat cycles,
Retorqued cylinder head blots and cylinder.
Leaked test (thank god I did, Leak between reeds and insulator block) Fixed with heat-temp silicone.
Did fifteen minutes of slow riding.
IMO, hard break in is best. There are a lot of people that believe this, and I've always done it this way. and have not had a problem.

 

[Blaaster]

What I did do is,
5 heat cycles,
Retorqued cylinder head blots and cylinder.
Leaked test (thank god I did, Leak between reeds and insulator block) Fixed with heat-temp silicone.
Did fifteen minutes of slow riding.
IMO, hard break in is best. There are a lot of people that believe this, and I've always done it this way. and have not had a problem.

I respect your opinion, but hard break in tears deeply into the crosshatching on the cylinder wall, owing to the rings being forcibly pressed outward, which puts extra strain on the ring lands.

Removal of the crosshatching robs the new rings of lubrication which is very nessessary for perfect bedding.

A motor that is broken softly retains more crosshatching, therefore provides lubrication for the rings for a greater period of time.

 

[Wifesblaster]

I respect your opinion, but hard break in tears deeply into the crosshatching on the cylinder wall, owing to the rings being forcibly pressed outward, which puts extra strain on the ring lands.

Removal of the crosshatching robs the new rings of lubrication which is very nessessary for perfect bedding.

A motor that is broken softly retains more crosshatching, therefore provides lubrication for the rings for a greater period of time.

Never heard it expained that way. I have always took it easy after heat cycles, at least a tank. Thanks for the explanation. Rep given.

 

[gb blaster]

I respect your opinion, but hard break in tears deeply into the crosshatching on the cylinder wall, owing to the rings being forcibly pressed outward, which puts extra strain on the ring lands.

Removal of the crosshatching robs the new rings of lubrication which is very nessessary for perfect bedding.

A motor that is broken softly retains more crosshatching, therefore provides lubrication for the rings for a greater period of time.

Learn something new everyday! I knew to take it easy but not exact reason. Why!

 

[beastsr20]

Okay, so I took your advice, Gave it a tank of normal not crazy/aggresive riding. On the second tank I proceeded to do a plug chop. I did it with a new plug and then an old plug. 6th gear full out, switched off and pulled the clutch.

The new plug appears to be reading lean, no change in colour at all. But the old plug stayed a nice chocolate brown colour. So I don't know what to make of it. Seems like I can never do a plug chop correctly. Is it possible to be running lean with a 330main in?

 

[Awk08]

you cannot use an old plug, once it's colored, it's colored.

are you running wide open throttle for long enuf ?
at least 10 seconds at WOT is required.

has it been proven leakproof with a leakdown test ?

 

[gb blaster]

I agree with Awk if done correctly the NEW plug would give the only results! Lean means a raise in jetting. Now did you releak test that motor after fixing the Reed block leak and letting the silicon set properly, may not have been your only leak.

If you can't ever get a correct plug chop. Remember that you must set your float height, idel speed, and be completely leak free BEFORE you try.

Then you must warm the bike up with old plug. Throw a fresh plug in and go WOT in each gear and stay in 6th WOT for at least 10 seconds like Awk said. You have to open the main jet circuit to get a correct chop.

 

[Blaaster]

That motor has to be pulling strong during the WOT run.

You have to use a new b8es plug, but if a ring is not showing on the plug in a leak proof motor, you are too lean.


Before you make the plug chop run it is important that the float level is correct, the idle is set correctly and there are no air leaks in the system, otherwise the smoke ring may lie about the AFR.

WHEN ALL OF THE ABOVE ARE CORRECT PROCEED WITH THE FOLLOWING.

Warm up motor to operating temp.

Fit new B8ES plug, ride through the gears and hold WOT in 5th or 6th gear for 10 seconds, or as long as you can safely.

Switch off the motor and pull in the clutch, apply brakes to come to a stop quickly.

Take the plug out and replace the old one for the ride home.

Carefully cut the threaded end off the plug to expose the insulator.

There should be a smoke ring of a cardboard or biscuit colour around the insulator.

If it is non existant or a very light colour, you are lean and require a larger main jet.

If it is a lot darker you are rich and may go down a size in main.

I prefer to run a little on the darker side, I may loose a little power but it is worth it for the peace of mind that I won't need a rebuild so soon.

http://www.blasterforum.com/do-yourself-20/how-plug-chop-38674/

http://www.blasterforum.com/engine-13/plug-chop-how-vid-48226/

This is a good to go plug.

This one is a little rich, but I would run it, I like to be on the safe side.

You have to get up a reasonable speed so that you can get the motor to pull strongly.

Then hold it Wide Open Throttle (WOT) for 10 secs or as long as you can.

The idea is not to get speed but to make it pull strong at full throttle to get onto the main jet circuit.

I find I can safely do it on a short run by applying the brakes some.

If you have not enough room you can use 4th or 5th gear with good results.

 

[beastsr20]

Thanks heaps for the advice. My motor is definitely leak free. And ive never felt it this fast before. Pulls so damn hard. Everyone was shocked. I think I didnt hold it in 6th long enough. I will retry it. Do you think it can be lean with a 330jet? The compression is 140. Hasnt been wildly ported I dont think. Still would not go over 60mph but fk it got there quick. I was looking for more gears lol

 

[Blaaster]

Thanks heaps for the advice. My motor is definitely leak free. And ive never felt it this fast before. Pulls so damn hard. Everyone was shocked. I think I didnt hold it in 6th long enough. I will retry it. Do you think it can be lean with a 330jet? The compression is 140. Hasnt been wildly ported I dont think. Still would not go over 60mph but fk it got there quick. I was looking for more gears lol

Reading this post leads me to believe that you could be on the razors edge of jetting and slightly lean.

Drop in a #340 and try again, even if it takes you to the rich side you should not notice any drop in power.

60mph is a fair speed for a Blaster, gearing should provide a little more.I:I