Derbi variating too fast

I think it is

Here's a glamour shot

IMG_20200430_185005714.jpg

Derbi cult is real. This poorly tuned stock top end bike is so comfy and quick

Re: Derbi variating too fast

EH 📣FCC of the QCB /

? Hard to tell with no load on the bike. If it’s launch sux try lighter weights.

Re: Derbi variating too fast

* wormdirt * /

> EH FCC of the QCB Wrote:

> -------------------------------------------------------

> ? Hard to tell with no load on the bike. If it’s launch sux try lighter

> weights.

Word. I've just seen Jbot suggest revving it on the stand to see if the contra spring is toast

I'm sitting at 36g (it's a 6 roller)

I have a set of 5g in the mail

Re: Derbi variating too fast

Totally normal JBOT /

It all depends on where the pipe hits and what your gearing is. . Stock ex?

Stock low revving bikes variate fast on the stand because they have weak springs and heavy weights

Re: Derbi variating too fast

* wormdirt * /

> JBOT Admin Wrote:

> -------------------------------------------------------

> It all depends on where the pipe hits and what your gearing is. . Stock

> ex?

>

> Stock low revving bikes variate fast on the stand because they have weak

> springs and heavy weights

The exhaust is a Puch black pipe from treats but stock otherwise

Re: Derbi variating too fast

tuning a variator needs a fair amount of precision. I doubt just dropping to 30g is going to be the magic number.

I tune with a few sets of these this set plus the 5g you ordered would allow you to tune from 15g with 3 5g rollers to 54g with 6 9g rollers. Every derbi I've had, granted only one of them was a stock cylinder and it's a start 3, have fallen between 21-27.5g total weight. the variances mostly due to different contra springs and ramp plates. (edited)

Re: Derbi variating too fast

Dirty30 Dillon /

Those polini weight sets are the truth.

Re: Derbi variating too fast

* wormdirt * /

Ok cool, roller sets and a new belt are ordered. Loving the derbi and variator set up, way better than digging into a e50 clutch over and over again

Re: Derbi variating too fast

todd amundson /

Man that front end looks thwacked

Re: Derbi variating too fast

Fun Fact. You can jam blobs of silicone or bb's in hot glue or all sorts of stuff in weights to try and fine tune them if you don't have a tuning set

Can also sometimes just drill out the insides as well if you can set it up in a drill press and do it consistently

Also get your self a little cheap scale.

Re: Derbi variating too fast

Totally normal JBOT /

> Joel P Wrote:

> -------------------------------------------------------

> Fun Fact. You can jam blobs of silicone or bb's in hot glue or all

> sorts of stuff in weights to try and fine tune them if you don't have a

> tuning set

>

> Can also sometimes just drill out the insides as well if you can set it

> up in a drill press and do it consistently

>

> Also get your self a little cheap scale.

Yes, I use dowels and wire.

Can tune weights to whatever you like with garbage jammed in, or drill em . Best bet is sometimes to only use 3 weights, and increase their weight by 50% +

Re: Derbi variating too fast

Emil Kniemel /
83FFF9F8-4BB2-45A0-8901-E3F850349269.jpeg

I dunno if its stock but my yellow TJT weights are tapped and have set screw in them to add (or subtract if removed) weight. Pretty kewl. 21+ gs seems so high to me??

But then again im brand new to derbi. I think hobbit was always around 14-16.

I was doing some minute tuning from 15-17 on my derbi.. like percentages of grams and was feeling differences. I decided to drop down to 12.xx and wow. What a difference.

Re: Derbi variating too fast

* wormdirt * /

> todd amundson Wrote:

> -------------------------------------------------------

> Man that front end looks thwacked

It's not bad, no support means it has a little wiggle. The frame isn't mine so I'm not doing a ton of wrenching on it. Just a loaner with my motor on it till I finish my frame n shit

I have a weed scale and I got all the weights the same to .1 grams

Some of them were .4 off

Really I need to lighten the weights because it looks like it jumps to 75% fully variated in like 15'

Re: Derbi variating too fast

Emil Kniemel /

> Wesley Ambrosini Wrote:

> -------------------------------------------------------

> > todd amundson Wrote:

>

> > -------------------------------------------------------

>

> > Man that front end looks thwacked

>

> It's not bad, no support means it has a little wiggle. The frame isn't

> mine so I'm not doing a ton of wrenching on it. Just a loaner with my

> motor on it till I finish my frame n shit

>

> I have a weed scale and I got all the weights the same to .1 grams

>

> Some of them were .4 off

>

> Really I need to lighten the weights because it looks like it jumps to

> 75% fully variated in like 15'

Just take out 3 of the weights and give that a try until your weight set comes.

Re: Derbi variating too fast

I never weigh them individually, always put them all on the scale together. Tuning with a tach and speedometer is so much better than just ripping down the block full speed and switching back and forth between paying attention to the road and watching your variator.

Re: Derbi variating too fast

Totally normal JBOT /

You should always weigh them individually and totally. Often the stock weights are off by a significant margin

Re: Derbi variating too fast

> Daniel '' Wrote:

> -------------------------------------------------------

> Tuning with a tach and speedometer is so much better than just

> ripping down the block full speed and switching back and forth between

> paying attention to the road and watching your variator.

True, I feel like I could’ve saved a boatload of time in the past by trying to tune variators by feel instead of having solid numbers to go to. That said I’m a big fan of going light with the weights and making a line with a sharpie up one cheek. You can ride w/o constantly looking down to check your variation and you can usually get a pretty good idea of where your belt’s going to by how high the mark is worn off. Go heavier from there and you’ll have the lightest weights possible while still fully variating.

Re: Derbi variating too fast

Emil Kniemel /

> iskra chornia Wrote:

> -------------------------------------------------------

> > Daniel '' Wrote:

>

> > -------------------------------------------------------

>

> > Tuning with a tach and speedometer is so much better than just

>

> > ripping down the block full speed and switching back and forth between

>

> > paying attention to the road and watching your variator.

>

> True, I feel like I could’ve saved a boatload of time in the past by

> trying to tune variators by feel instead of having solid numbers to go

> to. That said I’m a big fan of going light with the weights and making a

> line with a sharpie up one cheek. You can ride w/o constantly looking

> down to check your variation and you can usually get a pretty good idea

> of where your belt’s going to by how high the mark is worn off. Go

> heavier from there and you’ll have the lightest weights possible while

> still fully variating.

i just ordered a tach but i think i was able to tune it pretty close by feel as well. granted i was looking down to check variation but also do the marker technique. i go the lightest i have and check top speed. then i go heavier than i think and so i know it should be between the two.

i have found that while tuning, definitely use that retaining washer. my trials were kind of messed up since the nut was unscrewing a little sometimes and was making the variation inconsistent.. until one time it flew off and my nut, plate, guides and weights all flew off.

luckily i was just pulling into my neighborhood thinking the bike felt weird and was able to find everything.

Re: Derbi variating too fast

For most performance applications you want to run the lightest contra spring you can get away with and as light of weights as possible.

Heavier weights cost power and so does a heavier spring.

The sharpie trick does work to some aspects.. I personally like to rig up a gopro and go for a drive with it capturing the vario the whole time.. You can then easily see if it is shifting too early or your not getting full travel and need to space or cut down some shims to get everthing groovy.

Re: Derbi variating too fast

Dirty30 Dillon /

> Joel P Wrote:

> -------------------------------------------------------

> For most performance applications you want to run the lightest contra

> spring you can get away with and as light of weights as possible.

>

> Heavier weights cost power and so does a heavier spring.

X100

People slap mongo contra's in bikes thinking it will help them in some way, but really it's typically overkill.

Re: Derbi variating too fast

A heavier contra spring is really nice for a quick down shift for ripping up hills, but it does heat soak during longer rides or after ripping through the hills causing it to shift about 1k lower than usual.

Re: Derbi variating too fast

* wormdirt * /

Just got some of the weights in today.

I just blindly slapped a set a 4g in there. Way better pickup, solid derbi lurch

Top speed feels similar

I'm putting my RPM tach on there when the other weights show up. Already this is awesome. No mess just rattle some nuts off and get after it.

Re: Derbi variating too fast

Emil Kniemel /

> Wesley Ambrosini Wrote:

> -------------------------------------------------------

> Just got some of the weights in today.

>

> I just blindly slapped a set a 4g in there. Way better pickup, solid

> derbi lurch

>

> Top speed feels similar

>

> I'm putting my RPM tach on there when the other weights show up. Already

> this is awesome. No mess just rattle some nuts off and get after it.

So it was worth $75 after all huh. Lol

Re: Derbi variating too fast

* wormdirt * /

> Emil Kniemel Wrote:

> -------------------------------------------------------

> > Wesley Ambrosini Wrote:

>

> > -------------------------------------------------------

>

> > Just got some of the weights in today.

>

> >

>

> > I just blindly slapped a set a 4g in there. Way better pickup, solid

>

> > derbi lurch

>

> >

>

> > Top speed feels similar

>

> >

>

> > I'm putting my RPM tach on there when the other weights show up.

> Already

>

> > this is awesome. No mess just rattle some nuts off and get after it.

>

> So it was worth $75 after all huh. Lol

$75 plus a few hundred in parts

But fuck yeah it was worth it for the motor alone. I'll probably post build pics when the frame starts coming together

Re: Derbi variating too fast

Emil Kniemel /

> Wesley Ambrosini Wrote:

> -------------------------------------------------------

> > Emil Kniemel Wrote:

> > So it was worth $75 after all huh. Lol

>

> $75 plus a few hundred in parts

>

> But fuck yeah it was worth it for the motor alone. I'll probably post

> build pics when the frame starts coming together

better than a few hundred than a few more hundred in parts! #derbilyfe

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