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to tune or not to tune?

Old 12-27-2011, 09:30 AM
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to tune or not to tune?

I bought a 97 SH here in Switzerland after wanting one for 13 years and I love it. I am a transplanted Californian. I put Heli Bars, a dark screen, Targa tank cover, Scorpion high slip-ons and Mich Pilot Power tires on it and it runs great. It pops some on decel with the throttle closed(no PAIR sys on Euro model)and I was greedy for more midrange and that`perfect`tune so I bought a K+N(uhoh) filter and a D-J carb kit. Now after reading all the wise info on the forum, I am fairly confused. The K+N will stay in the box for sure and I don`t know what to do with the carbs. I had good luck with these products on other(Calif. lean) bikes so any advice or opinions would be appreciated. I know that you have been over this before but the SH seems like kind of a special case when it comes to tuning and it would be nice to get rid of the popping and have the best midrange possible. Thanks MarkN
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Old 12-27-2011, 10:22 AM
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Well normally I recommend trying this before messing with a kit: https://www.superhawkforum.com/forum...-set-up-24769/

But I will also add that you can install the kit you have and many have had some pretty good results.

Personally I believe they have made some changes to the kit from the time I tries to get one to work for me (late '97)

Either way you choose to go, the popping on decel is caused by a lean lower end.
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Old 12-28-2011, 01:22 PM
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Popping on decel is also from PAIR, if it's not disabled. I find it difficult to believe your bike doesn't have PAIR. I thought they ALL did.
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Old 12-28-2011, 01:56 PM
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Originally Posted by Hawkrider View Post
Popping on decel is also from PAIR, if it's not disabled. I find it difficult to believe your bike doesn't have PAIR. I thought they ALL did.
In Europe the VTR's didn't have PAIR until 01... I have helped set up several bikes, and helped disable the PAIR on the newer bikes, but so far none of the pre 01 bikes even have the valves on the heads, the mouldings are there, same as the "dummy" CCT mouldings, but no holes... I can snap a pic sometime if you want...
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Old 12-31-2011, 03:19 AM
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Thanks

Thank you 8541Hawk,Hawkrider and Tweety for your ideas and interest. I may try the needles and pilot jets from the kit but I am hesitant to drill the slides and probably will plug one hole in the front slide as that seems more logical to me. Happy New Year from Switzerland. Mark Nolan
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Old 01-01-2012, 12:17 AM
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I think Dynojet doesnt contain pilot jets, only main jets are here. But it is not problem do buy it somewhere, search for Keihin N424-21, or buy it here http://cgi.ebay.co.uk/KEIHIN-CARB-PILOT-JET-35-38-40-42-45-48-50-52-55-58-60-/130484446234?pt=Motorcycles_Parts_Accessories&hash =item1e617aa41a

From some experiences original pilot 45 is sufficient, as Dynojet kit with washable filter gives good results.

I have full arrow exhaust and bought BMC filter and Factory Pro kit 1.1.
Final setup is paper filter with Burnie Morgan mod (big improve in low-end and mid rpm vs BMC filter), 180 182 main jets, FPro needles, 50 pilot jets, plugged hole, and shimmed needles (dont know how much).
With BMC there was better top-end, but I prefer lower rpm. Currently it is running pretty rich, so plan for the spring is: smaller jets 178 180, pilot jets 48, velocity stacks and some tuning. I hope I will get good results and better consumption

For shimming needles, I will try to follow this write up from HawkRider:

"The tricky part is you want the rear raised .5mm higher than the front.
This is just a starting point as some bikes run better with just .5mm\1mm combination while others might like a 1mm\1.5mm set up and others run 1.5mm\2mm final configuration. The key is the rear is raised .5mm higher than the front."

edit: or maybe this comes from 8541Hawk, not sure ...


Last edited by Stephan; 01-01-2012 at 03:59 AM.
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Old 01-01-2012, 12:32 AM
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Originally Posted by 8541Hawk View Post
Well normally I recommend trying this before messing with a kit: https://www.superhawkforum.com/forum...-set-up-24769/

But I will also add that you can install the kit you have and many have had some pretty good results.

Personally I believe they have made some changes to the kit from the time I tries to get one to work for me (late '97)

Either way you choose to go, the popping on decel is caused by a lean lower end.
Just a point, Dynojet kit for Europe is different from US, as bikes have different carb setup. Dont know exaxtly where is the difference but there are bad experiences with Dyno Jet from US. I bought US kit Factory Pro, and it didnt work as I expected (big hole in mid range). And I wrote some mails with Roger Ditchfield and he recommended Dynojet as well.

This is my dyno after assembling Factory Pro kit and BMC, now after adjustments it is better, second curve is with smaller jets and paper filter. It is for illustration, this tuning was not good work. Numbers are for rear wheel.


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Old 01-01-2012, 12:10 PM
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Thanks for the info Stephan! I did buy a US D-J kit(uhoh again). I think that I will quietly put the kit in the drawer with the K+N and buy the 48 pilot jets, plug the hole and shim the needles. The bike runs really well and I don`t want to mess it up, just get it as close as I can to perfect. You guys are really a great help. Anybody want a K+N and a D-J kit cheap?? Happy New Year, Mark
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Old 01-01-2012, 12:38 PM
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Originally Posted by Stephan View Post
Just a point, Dynojet kit for Europe is different from US, as bikes have different carb setup. Dont know exaxtly where is the difference but there are bad experiences with Dyno Jet from US. I bought US kit Factory Pro, and it didnt work as I expected (big hole in mid range). And I wrote some mails with Roger Ditchfield and he recommended Dynojet as well.

This is my dyno after assembling Factory Pro kit and BMC, now after adjustments it is better, second curve is with smaller jets and paper filter. It is for illustration, this tuning was not good work. Numbers are for rear wheel.

Well to be fair, I do believe dynojet has changed the needle profile since I tried there kit and they can be made to work pretty good.

Though, also to be fair, to make a comparison to my set up thread you would need to ask Rodger what he thinks of the HRC\Moriwaki carb set up.

The reason I say this is that is what the thread I posted is based on.
The only difference is the needles. The stock needles are very good and work as well, if not better than all aftermarket needles except the HRC units, IMHO.

Also my set up is pretty cheap to try, a set of pilots and a little time and it's ready to go. If you don't like it, then buy the costly jet kit.

I guess I should get working on the HRC needle clone project I have been messing with.....
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Old 01-01-2012, 09:59 PM
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8541Hawk: I dont want to make comparison to your setup, this dyno was just for illustration how US FPro jet kit can work on europe bike. As US Dynojet is different as well, there can be some difficulties.

To deal with this hole in midrange shown above, Roger recommended adjust needle springs (new springs included in Dynojet too), or to plug one hole (this is HRC setup I believe)

I went with plugging one hole, as springs are little bit more tricky, and it works.

So I agree with your setup. Just new pilots, HRC setup, shim needles and maybe new main jets, no jet kit is needed. If IŽd know this before buying a jet kit ... :-)
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Old 01-02-2012, 12:09 AM
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Originally Posted by MarkN View Post
Thanks for the info Stephan! I did buy a US D-J kit(uhoh again). I think that I will quietly put the kit in the drawer with the K+N and buy the 48 pilot jets, plug the hole and shim the needles. The bike runs really well and I don`t want to mess it up, just get it as close as I can to perfect. You guys are really a great help. Anybody want a K+N and a D-J kit cheap?? Happy New Year, Mark
Youre welcome, beware of setting of pilot jets if you change it, you can have some difficulties (I had). I think best way how to set is Idle Drop Procedure described in manual. But there are people who know it better than me :-)

And if you will need bigger main jets and dont want to use Dynojet jets (different numbering - 180 KHI is not equal to 180 DJ), search for Keihin 99101-393.
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