UFO??

[1976RD400C]

I ordered the niche ones with the slide included for my 34mm carbs. I didn't want to grind away on my slides incase there is a problem I can just put my slides back in. My carbs work pretty well now so I hope I'm not disappointed. I also hope the needle circuit doesn't go out of whack too. Ordered smaller pilots like they suggest. It will be an experiment to see if there will be more power. My bike runs real well as is but I'm willing to play around. I'll report back. 

[m in sc]

I think so. Kinda makes their machined slides appealing, but they specify left side idle, and my 30s are a left and a right. I wonder if something could successfully be done with dirko or hylomar; something that would adhere to the slide but do no damage if it came adrift?

sombody did this to a triple, might have been jim hobbs? said it worked well. I'll never feel comfortable with an epoxy in the intake tract of anything on a street bike ( i know its been done but thats just me), but supposedly worked really well as well.

The aluminum ones that bolt in seem like a better solution to me.

the full slide is a good idea as well.

we'll see as i think we will all have a few versions to compare here soon. 

[Striker1423]

I think so. Kinda makes their machined slides appealing, but they specify left side idle, and my 30s are a left and a right. I wonder if something could successfully be done with dirko or hylomar; something that would adhere to the slide but do no damage if it came adrift?

sombody did this to a triple, might have been jim hobbs? said it worked well. I'll never feel comfortable with an epoxy in the intake tract of anything on a street bike ( i know its been done but thats just me), but supposedly worked really well as well.

The aluminum ones that bolt in seem like a better solution to me.

the full slide is a good idea as well.

we'll see as i think we will all have a few versions to compare here soon. 

I look forward to your report Mark!

[Organicjedi]

Two sets, three bikes. About $70 a bike shipped from the UK... Hard to beat that. I wonder how these would work in my 400?

[m in sc]

we're talking back and forth, im going to take some dimensions

[2steve]

Got some on my VM28's. A tad too small, but fills in most of the volume. Drilled a hole in the slide,  mounted with a wood style screw from the upper side and did a little material removal.   
Don't have good experience with or without to compare.  Was running plain 2.0's and was too rich right at throttle opening.  2.5's with UFO's are working great, really great.
Had to adjust the slides up for idle, (RD400).
Certainly something to try, IMO.

[m in sc]

I think the aluminum ones are def the ticket. if they don't work or i want to try,  just cinched the deal on a new 3d printer for work, not some bullshit hobby one either.

However, Bob in the UK seems to really be on top of it, he sent me some print dimensions to compare, i think he def took the thunder products concept to the next level by dialing in some give-a-shit.

[JB Weld]

Glad this has inspired you guys.

At the moment I am going to back off on the purchase and make sure I have the appropriate pilots to get mine running without. I've gone too long without riding on two wheels.

[SUPERTUNE]

I think so. Kinda makes their machined slides appealing, but they specify left side idle, and my 30s are a left and a right. I wonder if something could successfully be done with dirko or hylomar; something that would adhere to the slide but do no damage if it came adrift?

sombody did this to a triple, might have been jim hobbs? said it worked well. I'll never feel comfortable with an epoxy in the intake tract of anything on a street bike ( i know its been done but thats just me), but supposedly worked really well as well.

The aluminum ones that bolt in seem like a better solution to me.

the full slide is a good idea as well.

we'll see as i think we will all have a few versions to compare here soon. 

I did these in Jim Cannons H2 with his 30mm small body snowmobile carbs, mild port, re-milled heads and decks to get a real chamber design and with a few pilots changes worked great! Piston port motor now snaps like a RD reed engine.
I used some in Scott Turner's CB350 racebike and didn't work all that well, was too inconsistent at high rpm throttle snap off and roll on.
I haven't played with with them since...I do cut the slides to 3.0 with them in.
Been using TM34's on my yellow screamer for years and still have the VM34's and a set of ufo's out of Scott's bike if I want to try on them on my RD400...

Chuck

[m in sc]

my reasoning is im definitley getting a hiccup rpm related at around 5800. shocker, i know, right? . i absolutely can not tune it out ignition or jetting wise.  since the vms i have work so well everywhere else above and below, i figure i'll give this a try before moving back over to flatslides and kinda starting over. its more of a science experiment for me, but i think the more laminar flow under the slide will help. the 3.0 cutout probably isnt doing me any favors either   

[m in sc]

[SoCal250]

 

[2steve]

My UFO's have "3.0" molded into them but I'm using with the stock 2.5's.

[m in sc]

i just refuse to pay that for 2 pieces of abs plastic that may or may not fit my particular slide. 

[Td250]

The making UFO's is not such as easy task as one thinks; the fitment and subsequent jetting will probably create frustration to many users. Its a path not to be taken lightly.

Its much easier to buy and further develop your knowledge and fully understand the amount of the time it will take to get them to work effectively with your engine.