Where to start?

[Birddogg]

I'm not looking to get too crazy with this but I'm trying to get a few more years out of the old 90 before buying something bigger. I'm into CRF50s so I have a few parts laying around that I could possibly use to get a little more out of the quad to keep my oldest daughter interested but won't scare off my youngest.

Over the winter I added a DG bumper, ITP aluminum wheels, 16x6.5x8 Shredders in the rear, stock up front, and a Paioli shock in the rear off one of my old 50 setups. It raised it up about an inch in the rear, but really is a night and day improvement over the stocker.

I have an 18mm Keihin and a Trail Bikes intake I was thinking of adding that worked great with an old 88cc engine that I used in one of my 50s for years. It's just been sitting around collecting dust so I thought I might as well see what you guys thought before I started tearing into this.

I ordered a throttle cable today that would work with a Fast50s billet twist throttle that I picked out of the parts bin. Got home from work to start tearing things down then ran into my first stumbling block. What kind of petcock are you guys using? It looks like a standard Honda petcock would bolt onto the tank but it would be tough to get to. I want to keep the reserve feature since we still plan on trail riding.

The intake I'd be using looks like it would lower the carb toward the engine, but it would still be a little tight to access it. I know I'd have to chuck the airbox and go with a pod filter but will I loose a noticeable amount of torque? Enough so that the 18mm might not produce enough on top to sacrifice the low-end I'd be losing?

Is any of this worth the hassle?

[mcstore]

Why change to a 18mm carb when you have a 19mm carb stock?

[lilman]

if you are goning to trail ride it still i would opt for the air box i have two moded minis and the most frustrating thing about them is the stupid pod filters i hate them any water and your done.there is nothing more frustrating than getting watered out for the kids and its very hard on the motors i would go with some wheel spacers and a 114kit it wouls still have semi auto and be really reliable the 114 kit you can get cheap at your pitbike dealers

[Birddogg]

Originally posted by mcstore
Why change to a 18mm carb when you have a 19mm carb stock?


The 18mm that I have will flow a lot more air than the stock carb. The area around the slide is bigger and the choke isn't the butterfly style that's on the stocker. It slides up into the carb body when it's open.

I canned that idea anyway. I just ended up using an aftermarket twist throttle and CRF50 throttle cable on the stock carb. The kids never liked the thumb throttle. The reason why they would park it always because their thumbs got worn out.

The whole carb swap was going to lead to more problems than it was worth. It's physically larger, so it wouldn't fit under the tank with the stock intake. A shorter intake would drop it too low to mount to the airbox.

[Birddogg]

Originally posted by lilman
if you are goning to trail ride it still i would opt for the air box i have two moded minis and the most frustrating thing about them is the stupid pod filters i hate them any water and your done.there is nothing more frustrating than getting watered out for the kids and its very hard on the motors i would go with some wheel spacers and a 114kit it wouls still have semi auto and be really reliable the 114 kit you can get cheap at your pitbike dealers

I hear ya on the pod filters. I got the stock carb to work quite nicely now. After I got into it I found that the slide wasn't opening all the way, and I leaned it out a bit by dropping the needle down a click. The plug is looking like it's about where it needs to be. It was always a bit sooty but it's looking good now.