Jet Kit question

[mvalenti]

Looking at Jet kits for VM26's, and they dont seem to come with a whole lot for the money. A few sets of mains, needles & clips, but no pilot jets? Also, it seems one kit covers all gs850 models. Looks like I'd only be using the main jets and maybe the needles if they are different than stock. Anyone confirm if they are different? Also, anyone drill out thier own mains with good performance?

[Big T]

I'm confused

You list an 80 850, that has BS series carbs, not VMs

Never drill a jet, you can't maintain the precision needed for something you can buy for less than $5

[Agemax]

the needles are different, much better taper on them for mid range power. you shouldnt need to replace the pilots.
the 2 different size mains they offer are to compensate for what state of tune and overall condition of the engine.
as Big T says, drilling jets is a silly idea when you can buy them so cheaply

[MisterCinders]

Looking at Jet kits for VM26's, and they dont seem to come with a whole lot for the money. A few sets of mains, needles & clips, but no pilot jets? Also, it seems one kit covers all gs850 models. Looks like I'd only be using the main jets and maybe the needles if they are different than stock. Anyone confirm if they are different? Also, anyone drill out thier own mains with good performance?

I am confused.

If you have VM26s, why would you drill out the mains? Just change them for a bigger size. Main jets are cheap.

If your stock needles are adjustable, then you'd only need a kit needle if the stock needle has a bad taper. Can you order those needles separately?

[Steve]

Another cofused one here, do you have an '80 850 with a '79 head that uses the VM26 carbs?

The '80 850 came with BS32 carbs.

If you have VM26s, why would you drill out the mains? Just change them for a bigger size. Main jets are cheap.

Even if he has BS32s, main jets are still cheap.

.

[EvilEnfield]

I'm confused

You list an 80 850, that has BS series carbs, not VMs

Never drill a jet, you can't maintain the precision needed for something you can buy for less than $5

Nonsense, it has been done since the dawn of motorcycles, it is so easy it is unreal and takes around 60 seconds per jet, people have too much disposable income these days.

[EvilEnfield]

Looking at Jet kits for VM26's, and they dont seem to come with a whole lot for the money. A few sets of mains, needles & clips, but no pilot jets? Also, it seems one kit covers all gs850 models. Looks like I'd only be using the main jets and maybe the needles if they are different than stock. Anyone confirm if they are different? Also, anyone drill out thier own mains with good performance?

Yes I drilled out my jets with good performance. I didn't know it could be done or that it was easy, my dad told me and showed me how and that is how it used to be done. I commented on another thread about this just now but didn't want to confuse that thread anymore. As a courtesy for any future owners, sand off the numbers from the jets after you have altered them, check the accuracy of the bit sizes and your verniers by measuring a set of feeler gauges, check the number on your current jets corresponds to your bit by seeing which one fits snuggly inside it. Take your time and don't force the drill bit (held in a pin vice) and it will come out perfect, go up one size bit at a time, and be sure to measure each one, some brands are obviously better than others..

[mvalenti]

My 80 has the carbs from a 79. It also came with a set of cv's but no carb to head manifolds... So I kept the VM's on. Besides, I heard they were much easier to tune as compared to the CV's. Truth to it, I think I heard it here...

Drilling... I have precision machine lathes at work at my disposal as well and thought "creeping up to the right size" wouldnt be too much of a hassle. And loads of fun, cuz lathes are fun anyway... I guess I'm being stingy, dont want to spend 100 bucks on the kit... and then the hassle of waiting till it arrives... I know.... I have selective impatience...

The needles are new, Agemax, you say they are "different taper"? The needles (stock) have a very gradual fine taper. How do the jet kit ones differ? Thats the real question I guess... Are the needles tuned also?

Thanks guys.

[Agemax]

the DJ needles have a completely different profile to stock needles. look on the DJ website for more details.
are you running pods or a 4 into 1 exhaust? if so the dynojet kit is a must have

[mvalenti]

Not quite pods, and no to the 4 into 1.....

[Agemax]

with that kind of set up you will be extremely lucky to get it running correctly throughout the rev range

[mvalenti]

Thankyou.
At the moment I am getting very good response just over 1/2 throttle. Asfter that I need to feather it a bit as it is boggy. The exhausts although short, have been baffled. I am cruising around 50 mph in 5th @ 1/4 throttle.

[Agemax]

Thankyou.
At the moment I am getting very good response just over 1/2 throttle. Asfter that I need to feather it a bit as it is boggy. The exhausts although short, have been baffled. I am cruising around 50 mph in 5th @ 1/4 throttle.

so it runs like a pile of cr@p under 1/2 throttle and boggy above 1/2 throttle...........?
i wonder why?

[mvalenti]

I should have said, it idles fine, and it has great throttle response from idle to just past 1/2 throttle where it then bogs down a bit.

[MisterCinders]

I should have said, it idles fine, and it has great throttle response from idle to just past 1/2 throttle where it then bogs down a bit.

Then you need to do a mid-throttle chop and check the plug. Adjust the needle based on the result.