Rejeting the carbs... how much?

[Anonymous]

I am going to be putting on a set of straight through glasspacks on my 1982 gs850l, how many sizes should I go up? Is there anything else on the carb that needs to be changed along with the main jet? Thanks!-darren

[RJ]

Get yourself a Dynojet Stage III kit. The quality of the needles and jets is phenomenal compared to the stock stuff and you'll be able to fine tune the performance of your carbs with an increase in exahaust flow.

[Anonymous]

Cool, where could I find that? I've worked with dynojets on 4-wheelers and I agree they, they are a pretty sweet setup. Thanks-darren

[RJ]

I bought my kit from Motorcycle Accessories Warehouse. I don't have their web address off hand but you'll find them with your search engine. You can ocassionally find those kits on eBay but usually they're for 1100's or 750's.

[robinjo]

I believe they don't have a kit for the 850. :?
Maybe another member has done this already and an give you some settings like needle position and main jet/idle jet changes.

[Anonymous]

Maybe another member has done this already and an give you some settings like needle position and main jet/idle jet changes.

That'd be great, I think I found a dynojet kit on Dennis Kirk's site. But they're like $140 or something I'd rather just get a small assortment of jets from a 'zuki dealer and just stick with the original needle I guess.. I did some research on the site and seems with a set of pipes most ppl are going up about 8 #'s. One last question, how do I sync the carbs? Thanks for the help.-darren

[RJ]

You need to get yourself a carb synchronizer from any parts supplier. I got mine from JC whitney for like $40 I think. The procedure for synching the carbs should be in your repair manual. Basically the synchro tool measures the amount of vacuum each carb is pulling, and you adjust the carb linkage so that each carb is pulling the right amount.

[KEITH KRAUSE]

Speedy...Stage 3 is for use with pod filters, not a stock air box, or exhaust mod only.
There's a good chance you can just increase the main jet and turn your mixture screws out a little more. I would guess a full size (5) up on the mains and maybe an additional 1/2 turn out on the mixture screws for starters.
You have to test and take plug reads at different throttle positions to be sure. You spend the most time on the needle circuit, so you have to get that right to avoid running lean. Your needle can be shimmed, but I hear varying results about trying to shim up a needle. To get a true plug reading, mark your throttle and throttle housing at 1/3 throttle and ride a few miles at that position and then check the plugs. Main jet readings are taken at wide open throttle or at least above 3/4 throttle. Pilot jet readings can be taken after a few miles at a steady 30/35 mph in 4th/5th gear, but there will still be some overlap with the needle at those slow speeds. With all readings, do the "chop test" to get the most accurate reads. Be careful, we're talking hi-speeds to test the needle and mains.
The carbs must be synched first to get accurate/uniform reads too. Also, the filter and carbs must be in good order, etc.