Newbie upskills, and upgrades GT250R Muffler

[Gubb]

So my new Muffler arrived today, and it looked ludicrously simple to install, so I thought that I would give it a nudge, rather than get it done professionally like I had planned (I was quite worried about leaks).

Remember, it's only a 250!

Minus the Muffler:
http://www.youtube.com/watch?v=1N4yUjbS6-g

With the new one on:
http://www.youtube.com/watch?v=xt3L03l0jlQ

I'm utterly stoked at how easy it was to install, and it only cost me $340 including shipping!

[MattyP]

Sounds great! How can I get one?

[Gubb]

Got mine from here. (http://search.ebay.com.au/screaming-demon_W0QQ_trksidZm37QQfromZR40QQpqryZScreramingQ2 0demon)

[MattyP]

Just bought one :) Pretty damn good value, considering there are 'performance' GT250 exhausts on TradeMe for $470.

Can't wait :rockon:

[Gubb]

Was looking at a Cycleworks one for a while, but they were $550.

[Sully60]

Hubba what a Lad!
Starting your bike with no muffler,
Tisk tisk, you'd never catch me doing anything like that:innocent::msn-wink:

Sounds nice, all a twin needs is a few extra DB's in the lower frequencies to come alive.
Has it helped with the torque and midrange power?

[Gubb]

Took it out for a spin today, and it takes a little longer to get up to mid-range RPM, but once it hits 7500RPM, it bursts into life, and pulls almost twice as hard as it used to, right up to it's rev limit.

I hit the rev limit three times on the way home without even realising it.

Have ordered a K&N Filter to go with it, and will be looking at getting it re-jetted to get the air/fuel mix right.

Am so stoked at the difference such a simple modification can make though.

I'm learning more and more about it every day!

[EJK]

Faaar out! that is nice! It really gets the V-Twin sound out of that small 250 doesn't it? lol

Aa7 here in KB has a GT250 with a similar muffler and his bike sounds like a Ducati Monster :yes:

[carbacca]

Aa7 just took the baffles out of the stock muffler lol

[_Macka_]

heard it in person today sounds freaking awesome. next pay day i need to get on top of that

[Pancakes]

I tried a straight thru one on mine (made it myself and it was just 2" perf tube straight thru! and lost more low and mid than I likes to on the little bike. Does just keep on going waaaaay pas redline tho where the stocker chokes up near to 11,000 RPM. Have a 1 1/4" semi baffled one on now that is a nice compromise.

We need to do a group buy on these tho'. (can't post pic cos I already did here (http://www.kiwibiker.co.nz/forums/showpost.php?p=1169204&postcount=98)).

[blade1000]

you might want to get carbs re jetted as they run hot with after market mufflers on and the seaze one of the cylinders and thats not coverd under warenty

[Pancakes]

Already thought of that. Mine was damaged when I got hit and the insurance co. replaced it with this one. They are liable, I have it in writing. They can't do what is essentially a bad repair and have the part damage my bike.

[MattyP]

My new can arrived today and it's transformed the bike! It now feels like she has a soul (or should that be seoul? :) ).

I highly recommend a screaming demon pipe for Hyosungs. It only cost $300 including shipping. No-brainer to fit.

Stoked.

[Zuki Bandit]

Nice one Hubba. That sounds real sweet dude. Nice t hear those fatter notes coming through.

[disenfranchised]

I highly recommend a screaming demon pipe for Hyosungs. It only cost $300 including shipping. No-brainer to fit.

I ordered one last night.
Went for the irridium one just cause I like the look.

[WarlockNZ]

Just a note to anyone looking at putting a straight through pipe on the Hyo bag ..

I've been having a chat to Jon over at JFK adn he tells me that hes seen a lot of issues with the hyo from doing this.

The short story is that the rear cylinder runs too lean and causes damage ... if you want to put a straight through pipe on ... make sure you get your jets and filter adjusted to suit.

Especially if your caning the crap out of it.

[MattyP]

Just a note to anyone looking at putting a straight through pipe on the Hyo bag ..

I've been having a chat to Jon over at JFK adn he tells me that hes seen a lot of issues with the hyo from doing this.

The short story is that the rear cylinder runs too lean and causes damage ... if you want to put a straight through pipe on ... make sure you get your jets and filter adjusted to suit.

Especially if your caning the crap out of it.


What's the average price on this kind of work? I'm running the can at the moment and I'm TOTALLY in love with it. Warlock, I was the guy on the red 250r parked in front of you before we left for the cheesecutter ride.

[disenfranchised]

The short story is that the rear cylinder runs too lean and causes damage ... if you want to put a straight through pipe on ... make sure you get your jets and filter adjusted to suit.

Especially if your caning the crap out of it.

Any idea on how much use starts to cause the damage?
I was planning to bolt it on myself, and wait for the next service to get a professional mechanic to do the jetting thing.

Anyone out there been using a Screamin Demon pipe for a while without anything else being done? Had any issues?

[Pancakes]

Is the Screamin' Demon straight thru or just less baffled and bigger perf tube. I have a straight thru 2" pipe (not on the the bike daily!) and it is sooo fricken loud I doubt that any un-baffled ones are available. Totally unwarrantable, a cop would most likely stop you if you rode past giving it any cas at all. It is as loud as no pipe. I have a 1 3/4" less baffled pipe on mine and the shop said it would be fine. Warren from Virgin when I called about getting one done by him earlier said that he has done heaps and they don't HAVE to have a re-tune. It is never a bad idea tho and I'd always advise checking it's not too lean if you have the tools ( I have an EGO meter but need to tap a sensor in to my bike still cos it's carbied so doesn't come with one ). It does run noticably hotter with the straight thru pipe on as is pop's way more on the over-run. Also has bulk top end, just keeps on accellerating way past red-line, you'd need to balance the motor, do the valve springs and maybe the cams or just cam timing if you wanted reliability and any chance of making the most of rev's that are so far out of the bikes normal engine operating speeds.
The louder pipe I have on at the moment isn't quite as loud as the Virgin modded pipe and has no-where near the free flowing feel of the straight pipe so I can only guess without cutting it open that it still has a reasonable amount of packing and backflow restiction.

If it runs too lean it will run hot. Some of the things that can happen (depending on the weakest point in the chain etc, can really only be tested by trial to failure unless your a guru then your not tuning Hyo-bags your a race tech) would be first on my list hot exhaust valves causing the valve to melt or warp the stem and seize or shatter into the ignition chanmber. Detonation, melted spark plugs the list does on.

The more free flowing the pipe on these bikes the less low power and the more top end. They seem to run rich (most engines run a bit rich from the factory as a safety measure, the new sports bikes and performance cars are closer to ideal mixtures so will lean out with more airflow sooner) so get a pipe from someone who has done lots like Warren/Virgin or have it fitted by a shop and get them to note down the mix is ok for the pipe on your recept so your bike sounds a bit gruntier but don't go free-flow/straight thru cos then your look at a performance engine build and it's just not worth it.

[disenfranchised]

Is the Screamin' Demon straight thru or just less baffled and bigger perf tube. I have a straight thru 2" pipe (not on the the bike daily!) and it is sooo fricken loud I doubt that any un-baffled ones are available.

First thing I looked at when it arrived...and it's definitely straight through.

Was a bit of a bastard to fit.
3 of the bolts holding on the old muffler came out fine, but the last one (at the bottom between the pipe and the swingarm) had a stripped allen key socket, meaning it wouldn't turn, and also seemed to be rusted to the end of the exhaust.

I ended up having to cut the head off the bolt to get it off, which took several hours...poor tools, poor technique, etc..

Putting the new one on was simple though, and it really does sound good.
You can see a pic in the "Show us your 2fiddy" thread
http://www.kiwibiker.co.nz/forums/showpost.php?p=1300655&postcount=393

[Pancakes]

+1

Nice pipe! Crazy colours. Still waiting on a review of the twin disc upgrade too. You got the new master too a? Was it any different?

[Gubb]

Sorry that I neglected this thread, i've been stuck in Auckland for 2.5 weeks with no internet.

:whocares:

The pipe is straight through, and i've only had it out about three times since I put the exhaust on, i'm gonna get it re-jetted at it's next service this week.

Looked into aftermarket air filters, and haven't been able to find anyone that nakes one yet.

K&N and DNA don't make one yet, as the bike is not selling in massive numbers in the States (remember that if it isn't popular in the US of A, it isn't popular anywhere!)

Will keep you posted.

[325rocket]

heres what ive heard … don’t know if its true or not, feel free to comment …

a straight thru pipe isn’t ideal and can cause problems if you dont “rejett” to suit but you run a much higher risk of buggering things if you run a straight thru pipe and do change your air filter and don’t rejet.
If you just change the pipe your still quite restricted by the amount of air the standard filter lets in so you might be alright.
Put a different air filter in that flows more and all of a sudden you have a load more air and still the same amount of fuel. This is when you get problems with the bike running lean.

Please don’t take this as gospel as im basing this on my experience with turbo cars not bikes but I would think it’s basically the same principle but from what I understand bikes have a much smaller tolerance when tinkering with the exhaust etc.

Anyone in the know please correct anything incorrect here.

[Aa7]

Faaar out! that is nice! It really gets the V-Twin sound out of that small 250 doesn't it? lol

Aa7 here in KB has a GT250 with a similar muffler and his bike sounds like a Ducati Monster :yes:
Nah nothing as flashy as this for my communter hack ;) but my bike is a monster with all the hassles lately, it doesnt just sound like one :pinch:


Aa7 just took the baffles out of the stock muffler lol
Ssshhhhhhh!!!, they'll all do it now ahahahah Is your pipe the same as these ones carbacca if not what make is yours? your makes a nice sound thats for sure :)

I have heard a GT250R with the iridium Screamin Demon and it was alot deeper and nicer sounding. If i had the faired model i think that this is a definite upgrade that needs doing. if you run a commuter naked hack like me save your coin and just debaffle the original ;)

[Gubb]

heres what ive heard … don’t know if its true or not, feel free to comment …

That's pretty much bang on what I read before ordering the pipe. I had planned to re-jet, and add the air filter, but as I couldn't find a filter that would fit, I am still going ahead with the re-jetting on Wednesday next week.

Will let you all know how it turns out.

[disenfranchised]

All this talk of problems does have me concerned a little bit.
I did email the guys who sell them, and they did say that it shouldn't cause any problems, but definitely recommended rejetting.

I've just hit 7,000k's, and planned to get the shop to rejet at the same time as the 8,000k service....I'm assuming that there'd be some savings in labour charges from having both done at the same time?

I commute 20k's every day for work, and each day the popping/spitting noises have been getting more noticable, so I'm guessing holding out on the rejet for another 1000k's wouldn't be advisable??

I'm still loving the pipe though.
Every time I start my bike I smile, cause it sounds so much more grunty than it really is. :niceone:

Coming to work today I ended up behind a guy on an old Norton, and I'd have to say my little 250 sounded louder than his (probably a 750 single) :first:

[Gubb]

Possibly it's something to do with your current jet set up, the popping in mine has been pretty minimal, and I certainly haven't noticed an increase in it.

Then again, you've done almost twice the mileage I have, perhaps the stock injectors are a little worn?

Dunno, just some thoughts. Was always planning on having the re-jetting done at around the same time for myself, and as you said, getting them done at the 4000Km service to save on labour.

[WarlockNZ]

You'll be looking at about $130 odd for the Jets (including Labour) at JFK .. I had mine done today and holy shit man ... those boys know there shit when it comes to Hyosungs ..

I'll be giving them all my business from now on .. here's a link http://www.jfkjetskisandmotorcycles.co.nz/.

Tell them Murray sent you ... LOL ... I may get a discount out of it ... ha ha

eaqr8Dggb3o

[disenfranchised]

You'll be looking at about $130 odd for the Jets (including Labour) at JFK .. I had mine done today and holy shit man ... those boys know there shit when it comes to Hyosungs ..

Are you sure??...Their website makes them seem a bit confused :doh:

heh, I might give em a look tho...I've been using Red Baron for my services cause I bought the bike there.
Despite all the bagging they get on here for how much they charge for used 250's, their workshop department seems alright.
Will have to see how much $$$ they want to charge me.

[Pancakes]

You'll be looking at about $130 odd for the Jets (including Labour) at JFK .. I had mine done today and holy shit man ... those boys know there shit when it comes to Hyosungs ..

I'll be giving them all my business from now on .. here's a link http://www.jfkjetskisandmotorcycles.co.nz/.

Tell them Murray sent you ... LOL ... I may get a discount out of it ... ha ha

.....................



Did they dyno it or test it after with an EGO meter? Not for that price eh? (I'm not knocking, just thats cheap) If they have a good idea of what these need to run a straight thru pipe I may have to pay a visit. my home build bad boy is just sitting there staring at me!

[disenfranchised]

On the ride Sunday, I was crusing along at arround 85-90.
Went to accelerate and the bike just shuddered...so I relaxed the throttle.

It did it three times...so I changed up/down, did something (I can't remember the exact sequence)...and there didn't seem to be any problems after that.

Not sure if it's related to the new exhaust, or just a days riding harder than usual.

Could it have been some kind of misfire in the engine?

[Gubb]

Got it's 4000Km service today, when I walked back in, I overheard one mechanic telling another that "That's the best sounding Hyosung 250 i've ever seen"

:2thumbsup

Then again, there can't be too many Hyosung 250's with aftermarket pipes.

Anyway, Re: the re-jetting, he pulled the bike apart, and inspected the plugs, and said that going off the wear on the plugs, there is no need to re-jet at this stage. If I manage to get a hold of an air filter, it probably worth another look (I did find one here (http://www.bmcairfilters.com/VisModDetail.asp?ID=584), but they only ship to the US and Canada).

Until then, with the current setup, the bike is running in tip-top shape. I love the pipe, and love the bike even more with it on. Best result I could have possibly hoped for.

[MattyP]

*breathes a sigh of relief*

Thanks for sharing that, I feel much better :niceone:

[MattyP]

Had my first bin today, but the can survived unscathed!

Decided to head out through Clevedon and saw a sign saying "Clevedon - Scenic Route". I've never been that way before so I started off down the road and saw one of those signs with the squiggly line and arrow head denoting some twisties ahead - excellent!

About 5 mins down this road, having enjoyed some nice corners, I approach a deceptively tight, off-camber, right-hander. I was travelling pretty slow, but my brain still told me to chuck in some braking part way through the corner as the side of the road was approaching quickly. Looking back at it, I made the crucial mistake of fixating on the side of the road and what was about to happen. Sure enough, I run wide, tyres touch the gravel and down we go on the right side, sliding for about 2 or 3 metres. If I'd slid that distance again, me and the bike would have gone for a skate down a steep bank of about 10 metres.

I've had the bike (from new) for about 4 weeks and done 1500km on it. To see her lying on her side with the front indicator broken off and the fairing all scratched up made me sick. The front brake lever has a bit more of a curve to it now, but still perfectly usable. My ankle is pretty stiff and arms are sore from trying to life that heavy beast back up. I'm sure my foot would be in a much worse state if I didn't have my boots on. My right one took quite a hit and scrape under the bike.

Lessons learned:

1) Don't ride unfamiliar roads with too much enthusiasm until you've scoped the lay of the land.

2) Always, always look through to the corner's exit point.

3) When in doubt, lean further. My brain told me I couldn't lean any further, but I know full well that I have never approached the maximum lean on my bike (as evidenced by my rather large chicken strips).

3) Good protective gear is awesome. Wear it every time you ride.

4) Don't rely on car drivers (unless they're bikers, of course) to assist you when in predicaments such as this. Here I was, bike on its side, struggling to lift her back up whilst pointing downhill, perilously close to the drop-off of the bank , on gravel, and about five cars must have gone past without so much as slowing down. I realise it's not their problem to deal with, but it's a pretty rural road and a little help would have been greatly appreciated.

I rode the bike very cautiously home and apart from cosmetics and a sore ankle, both bike and I are fine. It really sucks scratching up something so new! That'll teach me for getting a fully-faired bike after 10yrs of non-riding :baby:

If my ankle is up to it I'll take her for a ride tomorrow to make amends, staying upright this time! :2thumbsup

[Pancakes]

Yeah matey, even the standard tyres can go over a long way.

Hubba Gubba, you have the straight through Screamin Demon and the stock standard setup a?

[Gubb]

Gutted Matty, at least your OK, and it's nothing majorly wrong with the bike. It sounds like you already learned from your mistake though, which is ace, as there's a fair few bikers that don't seem to learn that lesson for a long time.

You'll make a much better rider by acknowledging where you went wrong, and improving on your skills in the future. +1

And yeah Pancakes, spot on, bike arrives in Auckland on Saturday the 8th Dec, and my brother is out at Whenuapai, would be happy to show you/ go for a ride.

[Pancakes]

Wicked, sounds like a plan. Are you just up this way Saturday or would you be keen for a Sunday ride?

Disenfrancised? You out there? Want to go half of what we did the other day?

[disenfranchised]

Anyway, Re: the re-jetting, he pulled the bike apart, and inspected the plugs, and said that going off the wear on the plugs, there is no need to re-jet at this stage. If I manage to get a hold of an air filter, it probably worth another look (I did find one here (http://www.bmcairfilters.com/VisModDetail.asp?ID=584), but they only ship to the US and Canada).

That is bloody excellent news!!


Wicked, sounds like a plan. Are you just up this way Saturday or would you be keen for a Sunday ride?

Disenfrancised? You out there? Want to go half of what we did the other day?

Not good timing for me this weekend, especially not sunday, as I've got to be working most of the day.
Would be fun with just the 250's though...I might be able to keep up :eek:

[Pancakes]

Nah mate, not this weekend. The 8th (or 9th is way better for me if he's still up then).

That is good news about straight pipes on them a!, might have to put my homejob on for a cane if we go out.

[Gubb]

Sunday the 9th is best for me. I'm moving up permanently, the truck arrives on the Saturday, so it may be a little hectic then.

[disenfranchised]

The 9th could be a goer...will have to check my schedule (i.e. ask my woman!!)

[Pancakes]

The 9th could be a goer...will have to check my schedule (i.e. ask my woman!!)

Sounds like we're in the same boat!

Hubba, where are you moving to?

[Gubb]

Glenfield, on the North Shore.

[Pancakes]

Sweet, so are we doing the 9th?

[Gubb]

I'm keen, quite happy to follow while you guys show me the good roads.

[disenfranchised]

Well I asked my partner, and if it's a short-ish ride, she's quite keen to come along too.
But we'll definitely wuss out at the slightest hint of rain

[Pancakes]

Mmmmm, have to suck up to mah lady

[Vetran]

So guys did you have to end up rejetting or not?

[Pancakes]

Not yet but I have the name of someone reliable near me now that I'm gonna call after the holidays. Will post up the results if I think it's worth doing after talking to someone who knows more than me.

[Gubb]

Haven't had too yet, as I'm still waiting on the Air Filter to arrive.

Should be here mid Jan, then it's off to JFK for a re-jet, and a dyno.

[Vetran]

Ok cool I think I'll get one of these exhausts then they look and sound awesome. Just don't want to void my warranty then have it heat up seen some people say it might run lean.