Modifications - Performance Discuss aftermarket and DIY performance modifications

upjet?

Old 06-28-2013, 11:40 AM
  #1  
Member
Squid
Thread Starter
 
tomb393's Avatar
 
Join Date: Oct 2012
Location: Chicago
Posts: 82
tomb393 is on a distinguished road
upjet?

I got a 98 Superhawk wirh 6000 miles all stock. I am putting on Two Brothers Vale M2 exhaust on today and purchased a dynojet stage 2 kit.
I called a dealer to set up an appointment for jetting the carbs. They told me to return the jet kit because it will need upjetting, not rejetting. Can anyone shed light on this and tell me if this process would be advised or not?
Thanks!
tomb393 is offline  
Old 06-28-2013, 12:21 PM
  #2  
Senior Member
MotoGP
 
7moore7's Avatar
 
Join Date: Jul 2010
Location: Phoenix, AZ
Posts: 3,869
7moore7 is on a distinguished road
Yeah I know all about that. Up jetting is a common practice in which one decides to switch dealers because the first one spits out gibberish.

In all actuality, though, you may want to go through some of the "carb setup" threads on here before you throw a bunch of money into your bike. I'm pretty sure that what your dealer is talking about is using bigger main jets, which the Dynojet kit includes anyway. Your bike will be fine until you figure out exactly what to do. There is no rush, as aftermarket slip-ons have relatively little effect on your jetting. You won't damage anything and it won't run terribly. Once you do a little bit of planning, you can tune them in properly.
7moore7 is offline  
Old 06-28-2013, 12:34 PM
  #3  
Administrator
MotoGP
 
E.Marquez's Avatar
 
Join Date: Apr 2006
Location: Kempner, TX
Posts: 4,402
E.Marquez is on a distinguished road
What he said ^^^^

And please find a new shop to take it to... that one is either screwing with you or ignorantly providing you nonsense for information.

“Upjetting” , sure, let’s do that. (ok I suppose a third possibility is “upjetting” is a local term and the shop means well, and knows what it is talking about.. but ya have to wonder. They did get the send the DJ kit back part right though….LOL..)
E.Marquez is offline  
Old 06-28-2013, 12:47 PM
  #4  
Senior Member
Superstock
 
cybercarl's Avatar
 
Join Date: May 2012
Location: UK
Posts: 397
cybercarl is on a distinguished road
Also if this is a stage two kit, I think that involves drilling the air jets. This is something that is irreversible and not necessary with these bikes.

(:-})
cybercarl is offline  
Old 06-28-2013, 12:57 PM
  #5  
Administrator
MotoGP
 
E.Marquez's Avatar
 
Join Date: Apr 2006
Location: Kempner, TX
Posts: 4,402
E.Marquez is on a distinguished road
Originally Posted by cybercarl
Also if this is a stage two kit, I think that involves drilling the air jets. This is something that is irreversible and not necessary with these bikes.

(:-})
The DJ kit requires you to drill the slide, regardless of "stage" and I just spent an hour fixing a drilled slide.... Some may get good results with the DJ kit, but I never did after several Dyno tuning sessions
E.Marquez is offline  
Old 06-28-2013, 01:03 PM
  #6  
Senior Member
Superstock
 
cybercarl's Avatar
 
Join Date: May 2012
Location: UK
Posts: 397
cybercarl is on a distinguished road
I'm not talking about the slide hole and I have never had good results with these bike by drilling an extra slide hole.

The OP mentioned stage 2 not 1. IIRC I think stage 2 Dynokits require making the main air jet at the top of the carb larger. The same air jet that flo commanders connect to.

(:-})
cybercarl is offline  
Old 06-28-2013, 01:09 PM
  #7  
Administrator
MotoGP
 
E.Marquez's Avatar
 
Join Date: Apr 2006
Location: Kempner, TX
Posts: 4,402
E.Marquez is on a distinguished road
Originally Posted by cybercarl
I'm not talking about the slide hole and I have never had good results with these bike by drilling an extra slide hole.

The OP mentioned stage 2 not 1. IIRC I think stage 2 Dynokits require making the main air jet at the top of the carb larger. The same air jet that flo commanders connect to.

(:-})
Got ya,, not seeing that in the DJ instructions I have.
http://www.dynojet.com/pdf/1185.pdf
...and it talks about "stage 1"
(a term I hate as it has no standard and not consistant) but there is no listing on Djs catalog of a "Stage 2" kit for the VTR Dynojet Jet Kits - Offering Motorcycle Jet Kits & ATV Jet Kits
E.Marquez is offline  
Old 06-28-2013, 01:49 PM
  #8  
Senior Member
Back Marker
 
Letsrideinsc's Avatar
 
Join Date: Jul 2005
Location: Santa Cruz, CA
Posts: 156
Letsrideinsc
^^^^ this was my understanding too. Better to not install it and work with the stock carbs.
Letsrideinsc is offline  
Old 06-29-2013, 12:56 AM
  #9  
Member
Squid
Thread Starter
 
tomb393's Avatar
 
Join Date: Oct 2012
Location: Chicago
Posts: 82
tomb393 is on a distinguished road
almost all good

Thanks guys! I had never heard this term "upjet" and is sounded suspect. The bike runs smooth through the rpms with the Two Brothers exhaust. The only issue is a little backfire when I let off the throttle. So it probably just needs a little adjustment. I will read the treads on that as suggested.
Thanks for the speedy responses. Oh and, appointment cancelled.
tomb393 is offline  
Old 06-29-2013, 06:24 AM
  #10  
Senior Member
MotoGP
 
7moore7's Avatar
 
Join Date: Jul 2010
Location: Phoenix, AZ
Posts: 3,869
7moore7 is on a distinguished road
Popping on deceleration is fairly common on these bikes, and can be alleviated by removing the Emiisions PAIR, balancing the carbs, and many have found switching to a size 48 pilot jet (the backfire being slightly lean from the stock size 45 jets) helps.

You'll find this in reading I'm sure!
7moore7 is offline  


Thread Tools
Search this Thread

All times are GMT -7. The time now is 03:46 PM.


Top

© 2024 MH Sub I, LLC dba Internet Brands



When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.