'01 Blaster Issues... Low end bogging, dies and wont start after an hour...

[Dc2ProductionS]

Ok so a few things I figured out in the ABSOLUTE BLISTERING COLD LAST NIGHT.

1. ITS COLD OUTSIDE. 13 degrees with a wind chill making it feel like -4 made my garage a cool 20 degrees. Even with my space heater in there for 45 mins before I started working, it only got to 32.

2. The Keihin carb that was on here IS ENORMOUS. The inside diameter of the Keihin literally swallows the OUTSIDE diameter of the new Mikuni carb. (28mm inside)

3. The air filter that was on the Keihin carb doesnt even come close to fitting on the Mikuni.

4. Its still ridiculously cold outside.

5. The manifold that bolts to the head of the engine is obviously way too big as well from the Keihin.

So back to the parts department it is. I removed all of these parts with Mike (my friend who works at rec shop) and he will be picking up the following. I also pulled the reeds so they could be inspected as well.

- New Manifold to match Mikuni Carb to head
- New Air filter to match Mikuni Carb
- New reeds? Maybe just cleaned? Idk, Mike said he would take care of it. Lol

Mike's boss used to build and race quads and he inspected the carb I purchased. Saw no issues. The main jet that came in it was a 97.5. Walked right over to the jet drawers and pulled out a 105 and a 110. Advised to start with the 110 and plug chop. Go from there. Advised to leave the pilot as is for now.

Not being able to mate anything together, project was put on hold for a day or two until we can get a proper filter and a manifold. Mike said the odds are pretty good they will have those pieces in stock so we will see what happens.

With the carb being that big, it makes me wonder what made previous owner use that? Was it just a carb he had available and used it to make it run? Was it used as a drag setup? Pinned WOT she runs great.. lol. But as this whole thread started, down low she breaks up alot and boggs down. Only time will tell once I get this new carb setup on. Im thinking Im going to lose a bit of that top end going to the smaller carb, but the torque I will gain in the low end and clean RPM will be worth the loss of a little top end. There is barely a time Im even getting into 5th WOT. Stay tuned and I'll be back with some more info. I gotta take a picture of the jets for you guys to see as well.

ITS STILL COLD!

 

[MURPH]

VM26 ROUND SLIDE CARBURETORBETTER QUALITY

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did anyone else catch that lol

 

[bansheedave]

Any updates?

 

[Dc2ProductionS]

Any updates?

The intake manifold was in stock, the air filter pod had to be ordered. and new plugs are always on deck. It has been bitterly cold here in NY. Im hoping to get everything all together and squared away tomorrow. Reeds were also cleaned up and going to clean out the port they sit in as well.

SHES ALMOST COMPLETELY NEW... LOL

 

[Dc2ProductionS]

SO! UPDATE TIME!!

Ran a couple of tests, tried a couple of different jets and I think we are finally in the $$$...

First off for anyone else ordering this carb, the main jet it comes with is a 97.5. Not exactly sure on what the pilot size is. Didnt mess with it. It fits into the stock OEM boot with a little bit of wiggling but nothing extraordinary. When I first tried the carb as it came out of the box, it seemed a little sluggish in the low end and once powerband hit, it was like a turbo. BOOM. blast off. However although tons more power, it was still breaking up a little. Not as clean as it should be. Talked with Mike's boss and he recommended upping the Jet size. Gave us a 105 and 110 as I stated above. Went to the 110 and the low end DEF felt a bit better, but now once into powerband in 3rd and 4th it was starting to fall on its face. So I pulled the plug and it looked like it was burning a bit lean still. While I had the plug out this time, I had a compression tester handy and got a reading of 147. PLENTY of compression. Put in a new spark plug, and changed the jet to 115.


And then ladies and gentlemen...... I almost sh*t my pants. THIS is how a Blaster is supposed to feel. Good god does it feel amazing. Literally roasted my tires on the road through 4th gear. So good that i roasted the tires so much in 5 minutes of excitement that I opened one of the cracks on the sidewalls of one of the tires a bit and it didnt want to hold air any longer.

Luckily I have a set of brand new tires that I have been waiting to mount once this baby was 100%. Im scared to see what this baby is going to do once she gets some grippy tires on the back. I have a feeling that the front end will never be on the ground.....Once I can get some good straight pulls on her Im going to do a plug chop and see exactly where Im at with the tuning.


Here a little vid of Mike burning em all the way to 4th gear!!!!




But I must say... My smile is beyond ear to ear with how shes running...

 

[jus_me]

Don't know how I missed all this . Glad to see you got her running.. Wish I would have seen this earlier as I have all the carb parts you originally needed and would have gave them to you for almost nothing. < nm that but you need to do some PLUG CHOPS. Since you are not sure if or what pilot is in there?? you should plug chop different circuits on the throttle. The main jet is only for 25% of the throttle and that's top end. Is there a clip adjustment on that carb? She will run good on the lean side right before it seizes.. Id rather be a tad rich than lean..

 

[Awk08]

Glad you got it running good !
But......I had to remove your video as we have a helmet rule on here for pics and vids in motion.
Ride and risk as you please, but we promote safe riding on here, which includes wearing a brain bucket