Dynojet slide spring specs?

[John Orchard]

Hey Guy's,

Can anyone give me some specs on Dynojet slide lift springs please. Need to know the total uncompressed length and the wire thickness of the Dynojet items, thanks in advance.

Now if they are shorter than stock springs (with less coils), they will be stiffer than stock, for a same given wire thickness. Stronger springs will need more air speed in the venturi (higher rpm) for them to lift.

Slide lift holes, more, or larger, will cause the slide to lift quicker, once the vacuum overpowers the spring.

For hard sport or track riding, l want the slides to lift quick at high rpm. Hence: 2 or 3 holes and stiffer springs.

I recently glued one stock hole closed on each slide when fitting short stacks front & rear (from reading tips here), it is CRAP! I can feel the lag when snapping the throttle open, when compared to immediately before when l had two holes open per slide, with both short stacks.

I will be opening my second lift holes & cutting my stock lift springs, l did this to an older VTR that l had, it was awesome!

Thanks, John.

[Stephan]

Dynojet springs are way softer (20-30 %), than std springs. Dont have specs right now, if you really need, i can do some measurement till end of the week.
Btw, using dj springs as a template, I have batch of the springs lightly stiffer than oem made, and second batch 20% stiffer over oem (1st gen, storm from 2001 have different springs). Currently I am running front carb with stiffer spring and rear std spec - stage 1 modded engine. Not sure if it is the best I can achieve though, but next season I will play with blocking/reducing air jets and leave springs alone, it is running good.

Maybe try to get 2nd gen springs, these should be bit stiffer.

[John Orchard]

Amongst a ton of mods l have done to 2002 model, l cut 50mm off the slide springs, then stretched them 25mm (making them 25mm shorter than the stock 300mm springs). It runs sweet, but then it did before l cut them :-)

I have made some 'full radius' ram tubes, short front & rear, Pipercross filter, opened the airbox lid by 15%, l drilled the main jets to 1.85mm (that should make them about 190's) l have some Keihin 190's coming.

I fitted 48 pilots (2 turns out on the mixture screw) but l live about 1200 feet above sea level and it starts cold without choke, so l will go back to 45's at 2.5 turns out.

I had a problem with a blocked breather in the Chinese fuel cap, it ran lean off the chart at the dyno, l will report once l've changed the jets and after the next dyno run.

[Twitchy]

John, does this help?

So going back to my post in July 2015;

I measured the diaphragm springs after reading that DJ use a much shorter spring. The springs in the carbs are give or take 300mm (12"), the brand new units from Honda are 270mm (10 3/4ish").

I have taken delivery of a US spec DJ kit - 1185.002, and the springs are 137mm long;

I have not measured the gauge of the wire though.

[John Orchard]

John, does this help?

So going back to my post in July 2015;

I measured the diaphragm springs after reading that DJ use a much shorter spring. The springs in the carbs are give or take 300mm (12"), the brand new units from Honda are 270mm (10 3/4ish").

I have taken delivery of a US spec DJ kit - 1185.002, and the springs are 137mm long;

I have not measured the gauge of the wire though.

Wow ! Thanks, Springs with that much less wire would be so much stronger.

[Stephan]

John, does this help?

So going back to my post in July 2015;


I have taken delivery of a US spec DJ kit - 1185.002, and the springs are 137mm long;

I have not measured the gauge of the wire though.

Wow ! Thanks, Springs with that much less wire would be so much stronger.

Believe or not, these dj springs are softer than std ones, as I wrote above. That means if you compress the carb slide by hand, it returns noticeable slower.

[freeridenick]

I.I.R.C the whole point of the DJ kit is to get the carbs on the main jets as quickly as possible, hence the third lift hole. The welcome In section has a link to carb set up and the widely held opinion is that this isn't good for these bikes. The HRC setup only ran one left hole.

DJ needles, jets and stock springs can be made to work well.