wire splice mc21 without re-jet

**Mon Jun 02, 2008 10:05 pm » Post: #1 » Download Post**

ok some may think this is a silly question but here goes.
after doing the 2 wire splices would the bike still be reliable without re-jetting?
as i'm just getting my bike delivered this week i want to get the extra power but don't really want to mess about with it too much in bits. i'd much rather be out enjoying it (at least in the short term).
how about after drilling the airbox. i'd think this would need some work?
like i say don't really want too much messing if possible.
advice please.

**Mon Jun 02, 2008 10:31 pm » Post: #2 » Download Post**

No one sane is going to promise any engine modifiction is not going to require a rejet.

But its pretty unlikely just the wire spice will require anything, opening the airbox up will almost certainly at least benefit from a jetting tweak.
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**Mon Jun 02, 2008 11:03 pm » Post: #3 » Download Post**

+1
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**Tue Jun 03, 2008 1:05 am » Post: #4 » Download Post**

Stock settings are for a STOCK bike.
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**Tue Jun 03, 2008 10:09 am » Post: #5 » Download Post**

If you're not prepared to mess a bit, then don't mess at all!

I know how tempting it is to do a little mod and not spend time setting the bike up - I fitted new pipes and went for a ride. Siezed in two miles...

The question is, would you rather spend an evening messing for a nice power increase, or two weeks and two hudred quid waiting for a barrel replate and new piston?
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**Tue Jun 03, 2008 1:55 pm » Post: #6 » Download Post**

point taken. where can you buy pairs of jets rather than a whole kit?

**Tue Jun 03, 2008 7:35 pm » Post: #7 » Download Post**

honda uk just get the parts numbers from the parts manual on this site. the last three digits of the the part number refer to jet size so just substitute these for the size of jet you want. Cool

**Wed Jun 04, 2008 2:10 pm » Post: #8 » Download Post**

I order mine from here:
http://www.allensperformance.co.uk/index.html
They have always had the sizes I wanted in stock and they have been on the door mat the next day.

**Wed Jun 04, 2008 8:56 pm » Post: #9 » Download Post**

ok cheers everyone.
any suggestions on good main jet start size. (just a good place to start for wire splice and airbox mod not asking for perfect jetting just a good place to start from and work from there).

**Thu Jun 05, 2008 1:01 am » Post: #10 » Download Post**

o o

Last edited by DifferentStrokes on Mon Sep 28, 2009 8:11 pm; edited 1 time in total

**Thu Jun 05, 2008 1:58 am » Post: #11 » Download Post**

.
.

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**Thu Jun 05, 2008 8:38 am » Post: #12 » Download Post**

For just the splice and airbox mod, I'd guess at 165 to start with, but expect to find you'll go down from there. Read the tuning section before you start if you haven't already. As with all jetting advice, if you sieze it, it's on your head!

The safest way to set the bike up is on a dyno, and it'll be worth the money / time you'll spend doing it yourself. Plus, if it goes pop the firm doing it get to pick up the tab. Wink

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**Thu Jun 05, 2008 12:21 pm » Post: #13 » Download Post**

I think most dynos will have some form of disclaimer about those sorts of things Dave, but I could be wrong.

I was going to say start at 210 (biggest HRC U/L jet you can get!) to be safe, and work down! Laughing

You're a braver man than I, offering jetting advice! I've seen main jets both increased and decreased after a wiresplice/airbox mod!

Now, where's that "sitting on the fence" smiley?! Very Happy

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**Thu Jun 05, 2008 12:34 pm » Post: #14 » Download Post**

I've not used that many dyno's I have to say, and figured they'd be just like a normal firm, but I suppose it'd make sense for them to waive responsibility.

Anyhoo, how about we ask those with just the airbox / splice mod if any of them are using bigger than 180 jets?

We might at least be able to find a safe starting point by establishing the biggest jet out there...
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**Thu Jun 05, 2008 7:05 pm » Post: #15 » Download Post**

good idea. it would be nice to get somewhere to start from. biggest known with these mods would make sense.tyga mention a 150 main in their power up page.as i said just looking for a start point to give me an idea where to start from then plug chop from there to fine tune. cheers have been looking at the jetting section already. maybe start nearer 165 then to be safe.
dyno set up sounds good any recommended places in the south west area (somewhere nearish Bristol) that are good with 2 strokes?