RSM not accurate after 140 km/h

[fred_soo_88]

hie to all zerotohundred members... i just want 2 ask whether anybody have come accross this problem... is it normal or is it there is something wrong with my wiring..

i just bought an Apexi RSM the black limited... is accurate until about 135 to 140 km/h... after that it become inaccurate already.. like my meter shows 160 but rms is around 152 or 153 ... the differenence is not much is less than 10 km/h different..??

is it normal..?? or is there something wrong..?? because i read the manual they say when u reach high speed... is normal to have a little bit differents in reading .. by 10km/h.?? is it true or mine something wrong..??

 

[dome zero]

r u using ori rim o change to other size s.rim??

 

[fred_soo_88]

ori rim bro
is an evo 7 but i think the shop didnt enter the car weight and tyre pressure

 

[pcdr]

normal what,bcuz u got wind drag n everything,even gps is like 3% error or sumting,but i think ur rms is telling the more acurate reading,since its digital,i guess it calculate how many revolution the wheel doing and convert it into speed(kmh) juz like a machine that i know.

well try wit gps at the same time and u basicly will know the "true" speed.

 

[fred_soo_88]

bcoz evo meter until 180... the main reason i get the rsm is i want 2 cut the speed limiter and see what speed i go after 180..... but after 140 is not accurate edi ... means my top speed save is also not accurate right

 

[fred_soo_88]

to change to the ralliart califonia meter cost me rm2400.. too expensive .. rsm just 600 hahha ... and is digital i thought is accuarte

 

[pcdr]

no wait,i think the rsm is reading the true speed,even ur OEM meter is not accurate,the rsm is giving u the real speed(altho abit error)ya i know its devistating sumtimes to see the number gets lesser but u tried do a 0-100 wit gps and 0-100 wit timer and clock ur meter,u will see 0-100 wit gps or with a speed trap beacon is slower,its bcuz ur meter have their error.

lets juz say this,i did 250++ last week and my fwens gps(which i carried at that moment) inddicate 232 only,and my meter is digital,it calculate tyre revolution.

ur rsm meter got manual rite?mayb they got state the reading error

 

[fred_soo_88]

i read the manual already .... they say wiring may be wrong or before u install the rsm u have a speed limiter already .... and 3rd is when u reach top speed it is possible to be different around 10km/h ... i assume my wiring have no problem and i have no speed limiter before this .. so my problem is the third one..... but i want 2 get confirmation from u all.. if really there is such problem then mine is alright if cannot meaning my wiring have problem

 

[pcdr]

well if u wanna try,set a date this week,ill bring my fwens gps,we can have some unofficial drag too,wo0t

help u rectify the prob,if ur free la,no charge u money la,forum fwen,help help la

 

[fred_soo_88]

thanks bro.. but not so soon la .. just get the car havent fully control the car and havent really noe the car limits.. oso dono how 2 launch onli.. maybe 1 day yea... but act the main reason i fix the rsm is to see its speed... bcoz my meter onli 180.... i think the drag time is acurate .. just the speed onli im curious... .however thats the main reason i bought the RSM to see the speed more than 180.. but if the speed more than 180 is incorrect.. whats the point getting it...

 

[pcdr]

lol okay,i get ur point,we juz love numbers,normal....

boy wait till u get 299 on ur meter.....wooooo gila syiok man!

 

[fred_soo_88]

hah i cant la.. my car 90% stock .. i don want touch the engine and ecu... im scared... i prefer original car...

 

[g88]

if you using bigger rim the different might be more obvious but even with stock rim there is also different since RSM get your speedo reading from ECU and your analogue meter reading from wheel/gearbox is i am not mistaken.

What i can tell is the faster you travel the gab better analogue speedo and RSM is getting bigger and bigger...

Like i travel RSM show 90km/h but my analogue show 90++km/h or touching 100km/h...

Bottom line. It's NORMAL. Dun worry :)

 

[fred_soo_88]

meaning is normal ar bro..?? nothing wrong with the wiring..?? if like that who to believe..??? rsm or analog meter...

 

[g88]

meaning is normal ar bro..?? nothing wrong with the wiring..?? if like that who to believe..??? rsm or analog meter...

I believe RSM now since reading directly from your engine. If analogue then if you upgrade/downgrade rim size will get different reading...

That's why now if speed signal show 80km/h i will drive upto 80km/h +- 10km/h hehehe

 

[OTF-39]

i have a question here...

if u install RSM blue screen in ur car... and u take it off just like that (there's a socket conncting the wires at the middle of the black wire) what will happen to ur car? the car idiling will go crazy? basically the speed wire will get disconnected, so just wondering what are the consequences...

any sifu who ca answer this?

 

[g88]

i have a question here...

if u install RSM blue screen in ur car... and u take it off just like that (there's a socket conncting the wires at the middle of the black wire) what will happen to ur car? the car idiling will go crazy? basically the speed wire will get disconnected, so just wondering what are the consequences...

any sifu who ca answer this?

nothing will happen at all...you can plug it in/out when engine is running....

 

[OTF-39]

er.....actually i'm quite confused here...

RSM...how u install it is that u intercept the wires by cutting it and join back to the rsm unit. Some other wires u just tap it directly...

So my question again... if u ugplug ur RSM..... those intercepted wires will be disconnected isnt it? ( doesnt go through RSM unit anymore)

so when those wires got disconnected....what happen to ur car? The ecu will not get any feedback since the wires are disconnected?