Re: Need monoshock for impulse

Which location are you from?

Need monoshock for impulse

The stock rear suspension has given up after 8 yrs. Unable to source it from local A.S.S.

Checked the "thesparescompany", "safexbikes", "sniper"....

Any links please let me know.

Re: Hero Impulse ownership experience

819 is a better option and one of my friend was using it.

Re: Hero Impulse ownership experience

Is anyone using Timsuns? Which size is better for offroading? Was planning to invest in the 819's 90/90-19 & 110/90-17. Has anyone tried the 830's 110/80-17?

Re: Hero Impulse ownership experience

Okay then you tell me what did you do, are you saying that you bought the BBR piston, cam and springs for CRF 230 which makes it 240. so have you bored the stock impulse cylinder ?

Re: Hero Impulse ownership experience

YOU CANNOT INSTALL THE CRF150F KIT ON THE IMPULSE, WITHOUT THE KARZIMA ENGINE. the engines are totally different. You cannt replace just cyl, piston and cam. as you claim.

Re: Hero Impulse ownership experience

I am asking about the rear shock spring rate, Front i calculated its comes between .38kg/mm to .40kg/mm cause i dont have a big vise hence i am not able to do the rear calculation.

These are Zedling suspension pune, i am from pune only only bro have visited there place i am gonna get front fork internals from there only but rear i need dampening adjustments and that zedling doesnt have.

You didn't tell what exactly you did on your impulse, you bored the stock impulse cylinder to 67 mm ?

And i confirmed with the guy who did job onto his impulse for the CRF 150 F BBR kit of 2006 till present, he replaced the cyclinder, piston,cam and springs.

Re: Hero Impulse ownership experience

Ans: Combination of hand carry parts when visiting abroad and ordering via Ebay. I am not using the stock rear shock. to match the front fork (spring rate .38 kg/mm) travel of 285mm, new rear was made from scratch with a stroke of about 62mm vs OE (48mm) to give additional travel. Its a twin piston chamber shock which has separate valving for compression and rebound dampening and has been set up for my weight for desert racing. The new shock as you can see also has a preload adjuster which is missing in the original unit for adjusting SAG which was not possible before. Hope this helps. cheers.



----consecutive posts auto-merged-----


Impulse bottom end and crf (150/230) are totally diff. they dont share any engine parts whatsoever. my bike has a compression ratio of 11.5:1 using the BBR kit.

Re: Hero Impulse ownership experience

Nice!
Which carb did you upgrade to? The bs3 or bs4 of ns200... Pls share more details in the jetting, cdi, etc

Re: Hero Impulse ownership experience

So you ordered the CRF 230 big bore kit (piston,cam and springs) and bored the stock cylinder to 67mm ? what compression have got ? cause i read somewhere that CRF 150 F 06 onwards big bore kit which includes cylinder,piston,cam and springs making it to 196 cc and 9.8:1 compression is direct fit onto the impulse bottom end.

how you sourced the CR125's front (forks,both T,wheels and brakes ?) btw have you calculated the spring rate of rear shocks ? stock and xr's ?

Re: Hero Impulse ownership experience

Is anyone using Chest protectors for offroading? if so, which one?
I was thinking of getting the EVS F1 chest protector and later get the kidney belt and elbow pads.
Any suggestions?


Also my Impulse is out now and has evolved to Impulzma <3
I must say, it is bloody awesome.

----consecutive posts auto-merged-----

Hello, Ankit. Just got my Impulzma with ns carb out of the shop and my goodness it is on another level. I love it so much. It's torquey and easy to keep up with the domi and himalayan or even the Mojo. Need to spend more time on riding it, to see if any faults show up. Right now few more tweaks has to be done to get it complete. Speedo ain't working, need to find better brakes or change tyres, Swingarm bushes need to be changed and also need to add self motor to it. Once it is completed, will update more. Running shell 10w 40 oil.

Re: Hero Impulse ownership experience

[MENTION=75258]alinel[/MENTION] Thanks for the reply.

Looks like I have two options

1>Start studying about motorcycle geometry from basics.
or
2>Eyeball everything and pray it works

It is a project bike i want to build/modify.I will try to start a new thread for it.

Re: Hero Impulse ownership experience


Ans:

The karizma axel to fork top length and difference when compared to impulse will give you how much rise you can expect from the swap. The rear geometry is going to be a lot more tricky as karizma uses twin shock setup vs a mono for the impulse. Not only this, the impulse frame has a offset for the shock mount. which means that using the impulse swingarm on a karizma might need some serious work too.

Why not just us the impulse ? whats the purpose of this swap ? infact the exact same thing has been done with the xpulse from here, where the frame of the xpulse is very very identical to a karizma.

Re: Hero Impulse ownership experience

Forks: Forks like mentioned are from a 1989 Honda CR125 Mx bike (open cartridge showa 43mm fully adjustable for rebound and compression dampening) with about 10.5 inches of travel (265 mm). This specific model uses the same steering stem bearings to work on the impulse without any mods. 26 x 47 x 15 - 32005/26 if i recall the bearing size. (https://www.allballsracing.com/forkconversion - refer here for any such info)

[MENTION=75258]alinel[/MENTION]

I need your help.

I am in planning to swap Karizma Suspension with impulse.(Both front and rear)
Front and Rear rims will be 18 inch.

I am not clear with the geometry.


Both Karizma and Impulse have 26 degree caster.(Stock)
Trail on Karizma is 94 mm and Impulse is 99 mm.

Once I swap the front forks all these numbers will go for toss.

The caster and trail will change to say x and y respectively.
The above will effect the ride dynamics.

I will not have provision to change wheel base,also I do not want to alter fork length by any means.

The only thing I will have control is over rear shock mounting angle/length and this will allow me to
set one of the parameter caster or trail to stock Karizma.

So my questions
Is my method of looking at the whole thing correct?
If not what geometry parameters i need to check/follow to do the swap?

If yes,what should I match Caster or Trail length?

Re: Hero Impulse ownership experience

A: This is the BBR kit - https://bbrmotorsports.com/Products/...d=411-HCF-2301 , You can buy it from BBR directly or chose to order from Ebay.com which might be cheaper.Please note that You will need a professional to hone the cylinder in a proper lethe/machineshop/turning works ..

Forks: Forks like mentioned are from a 1989 Honda CR125 Mx bike (open cartridge showa 43mm fully adjustable for rebound and compression dampening) with about 10.5 inches of travel (265 mm). This specific model uses the same steering stem bearings to work on the impulse without any mods. 26 x 47 x 15 - 32005/26 if i recall the bearing size. (https://www.allballsracing.com/forkconversion - refer here for any such info)

Work involved :



As you can see. There is a fair bit of work involved. Now, the fork swap is something pretty straight forward if you have the entire kit like I did (Wheels, brakes, T clamps, Spacers, etc) however, what is critical with the impulse is to make sure that the geometry is set correct with the same or close to same as the OE specs. Castor, trail, wheel base etc. Also, another key metric is to ensure that the front and rear suspension have identical travel (6.8 inches F, 5.9 inches R for Impulse) to ensure that they compress and rebound at "Comparable rates". This meant that I had to have atleast 4 more inches of travel at the rear without increasing the seat height by the same which will end up making the bike really tall. So this is where the 1986 xr250r comes in. It has a different motion ratio (15mm closer than the OE swingarm at the pivot fulcrum, more about motion ratio https://www.quora.com/How-do-I-calcu...arm-suspension) by enhancing the stroke of the rear shock, as well as losing some unspring weight and gaining rigidity as its a aluminium unit. More unsprung weight has been lost using 1986 xr250r wheels (DID aliminium 1.65 & 1.85 vs Mild steel 1.85 & 2.15 for the original) and Hubs, which are made from magnesium ! The original rear shock in an impulse has a stroke of 48 mm. The shock we made has 62mm and with the change in ratio, it has a 9 inches travel at the back.

Hope this helps !