TWIRP Jetting Thread

Post by **AlisoBob** » November 21st, 2010, 4:25 pm

I only have the 1/2 TWIRP, so keep that in mind.

I ran a #42 pilot, DGN, and #170 jetting in my 41mm PWK / stock jug and reed cage 500. Ran pretty good everywhere ( from Pismo to Johnson Valley) Would ping sometimes, but not too bad.

A few days before the Elsinore GP, a bunch of us went out to Hodge Road to get some seat time before the GP. I went to break in my new "Roosty" top end.

Hodge is high desert , and its a warm day. Bike ran pretty good, jetting seemed a little off, but rideable. I didnt really have time to dick with it before the GP, I was just going to run it and see what happens.

So, the morning of the GP I know something isnt right.... Lake Elsinore is only a few hunderd feet above sea level, and its a cold morning. I pull the choke and the bike lights off in a few kicks. The instant I shut the choke off..... " Bwaaaaaaaaaaaaaaa" it dies. Choke back on , restart... run for a few minutes to get it warm...... "Bwaaaaaaaaaaaaaaaa", dies again.

WTF???? I run that Zip Ty Racing air screw, so I crank in all the way in (full rich) and crank er up again..... it runs with the choke off now, but really dosent like sudden throttle opening. The leanness I felt at Hodge Road must have been leaner than I thought, because it will hardly run now.

I run it until the rads are too hot to touch in the staging area, hoping to get enough heat in the motor so it will take the throttle at the start of the race. It does, and the race goes off without a hitch. The bike hauls ballz down the long straights, but feels kinda soft in and coming out the deep sandy corners. I tell Roosty about it, and he agrees it sounds kinda lean.

So today it stops raining, so I went out to bump up the mixture. Turns out I had a #40 pilot in it, so I put a #48 in there , reset the air screw at 1.5 turns out and drop the clip one position. Its now 2 from the bottom ( its was in the middle).

There , thats better!!!! Starts in a few kicks, idles with the choke off after a minute or two running. Throtltle response is back, but most importantly, I can chug it in 3rd down my street and whack the throttle and its got plenty of "Giddy-Up!".

So, whats this mean to other 1/2 TWIRP customers? Richen up your set up a little most likely. I also added V-Force III reed block at the same time I did the top end, not sure if this is a factor or not.

I'm pretty happy with Roostys porting now, it still will take a few more rides to reach my final tuneup, but richening things up a little ws a big step in the right direction.

http://www.youtube.com/user/500bigbore · November 21st, 2010, 5:53 pm

glen howell · Post by **glen howell** » November 21st, 2010, 7:01 pm

[/img]

seanmx57 · Post by **seanmx57** » November 26th, 2010, 2:25 pm

So can you comment on the power below 3000 rpm compaired to stock?

Slomo · Post by **Slomo** » November 30th, 2010, 4:01 pm

Glen... I thought Bob made an honest tech post about some work he had done. Why does it bother you so much that he is happy with the work he had done by Roosty?
Come on out to Hoonfest with your "trail" bike and let's no kidding see how it compares to others on this board. We can all actually ride singletrack and race up, down, and around whatever in the hell you want. I'll even throw my new AF that's been ported by neither of you into the mix. I'm not saying anything about my riding ability, so don't even start with that, because I'm not bragging nor complaining. I'm a nobody and that's cool with me.
So, what says everyone looking for the best available?
Put up, or shut up...........

glen howell · Post by **glen howell** » November 30th, 2010, 9:30 pm

the real story

[/img]

Post by **AlisoBob** » November 30th, 2010, 11:49 pm

glen howell wrote:The hoon put it togeather and called me and said he was very happy with it.....I have to be nice to him ( Bob ) to keep on his approved list .

Glen, what you sent me was a pile of shit, and if you sent it to this unknown customer of yours without reworking it, he would have thought it was shit work too.

Your best years are behind you Glen.... old trees rot at the top and your a classic example....and as far as you being "nice" to me, fuck that.

Your no longer on my "Approved List". I've tried to keep it nice by giving you the benifit of a doubt that the job you delivered to me was just one that got out to door, that shouldnt have.

But as this has gone on and on, it has become clear that your opinion is that delivering shit work is ok, and if you refuse it your labeled a whiner.

Fuck you Glen.... I refused your garbage, and now you've forced me into a position where your no longer welcome on my board.

Go pedal your crap somewhere else.

britincali · Post by **britincali** » December 1st, 2010, 12:22 am

Everything else aside Ive gotta say Ive got a problem with the public postings of PMs, they are their namesake PRIVATE MESSAGES

Not good form posting them up glen......

Post by **AlisoBob** » December 1st, 2010, 1:05 am

GSS = GLENS SHIT SUX

http://www.youtube.com/user/500bigbore · Post by **Roostius_Maximus** » December 1st, 2010, 5:18 am

Glen, tell me what in those pm's was bad talking anyone or what made any difference by posting it. I don't care that you've posted it, but you come off as a real douche to the other members.
I sent it as a pm so that it wasnt lost in a thread with other guys commenting in a conversation.

Mad Dog · Post by **Mad Dog** » December 1st, 2010, 6:43 am

britincali wrote:Everything else aside Ive gotta say Ive got a problem with the public postings of PMs, they are their namesake PRIVATE MESSAGES

Not good form posting them up glen......

x491

Slomo · Post by **Slomo** » December 1st, 2010, 7:06 am

Glen- It's interesting how you go off on tangents. Example is the last paragraph in your post. Telling me I can get involved and you'll say I'm the best and have the most is childish. There are plenty of self promoting riders here. I am not one of them. You were the one going off how you are pro, remember? The intent of my post was to get several machines on a ride so we could see how everyone's porting works in real world applications. If it involves some racing, I am down with that also. I'll even let others ride my bike to see how they like it. February in arizona... Can't think of a better way to settle everything.....

KE 336 · Post by **KE 336** » December 1st, 2010, 8:43 am

Damn! Another public pissing contest gone bad! Glen, I'm about as neutral on this as you can get as I don't know you or Bob personaly.
You had a customer that wasn't happy. That is going to happen in any business a time or two for whatever reason. The good thing is you made good and replaced the parts and customer publicly said you made good on your word. To me, that's what I would have remembered and don't see why this shit couldn't have ended there.
While Brit (in good fun) catches all kinds of shit around here, I couldn't agree with him more on the PM thing. Now if I ever need a cyl. done I'm going to remember that about this story instead of the part of you making good.

hoofarted · Post by **hoofarted** » December 1st, 2010, 9:22 am

seanmx57 wrote:So can you comment on the power below 3000 rpm compaired to stock?

I am curious about this too. IIRC, you mentioned the bottom being soft - is that b/c of the lean condition?

Tharrell · Post by **Tharrell** » December 1st, 2010, 12:27 pm

Hey, I don't want to get any of that piss on me but back to Bobs info, what is a TWIRP?

http://www.youtube.com/user/500bigbore · December 1st, 2010, 12:46 pm

Its an acronym for the porting design

Post by **AlisoBob** » December 1st, 2010, 1:15 pm

hoofarted wrote: I am curious about this too. IIRC, you mentioned the bottom being soft - is that b/c of the lean condition?

Yea... thing pulls like a sum-bitch now.

Since I added a new top end, porting, and a V-Force reed block all at the same time, its hard to tell what did what...

Power is stronger bottom to top.... maybe 10% more down low, 20% more up top...

I need longer sleeves for my jersey now....

blownbillybob · Post by **blownbillybob** » December 2nd, 2010, 6:42 am

[quote="KE 336"]
You had a customer that wasn't happy. That is going to happen in any business a time or two for whatever reason. The good thing is you made good and replaced the parts and customer publicly said you made good on your word. To me, that's what I would have remembered and don't see why this shit couldn't have ended there.

It's good business that glen replaced the parts and tried to make good on something bad BUT! He would have straitened the bore and still probably had the ball hone finish over a rough bored cyl???

Now that his approved vendor pages are gone you guys can't see the pics anymore , one of them was of his little cyl hone cabinet with a 500 cyl in it with the torque plate on and a ball hone sticking out, those pics were years old!!!!

seanmx57 · Post by **seanmx57** » December 3rd, 2010, 6:43 am

AlisoBob wrote:
hoofarted wrote: I am curious about this too. IIRC, you mentioned the bottom being soft - is that b/c of the lean condition?
Yea... thing pulls like a sum-bitch now.

Since I added a new top end, porting, and a V-Force reed block all at the same time, its hard to tell what did what...

Power is stronger bottom to top.... maybe 10% more down low, 20% more up top...

I need longer sleeves for my jersey now....

Sounds like your power improvement was mostly porting improvement.

What were you running for an intake set up before?

You old top end wasn't that bad by the looks. Was it still running good compression, like 150+ ?

Adam I'm curious regarding the $600 lower end porting added to the top end work. Does that yield similar results, just less improvement? Or is it an improvement in a certain part of the powerband?

Post by **AlisoBob** » December 3rd, 2010, 7:08 am

seanmx57 wrote: What were you running for an intake set up before?

Stock block with Carbon Reeds
You old top end wasn't that bad by the looks. Was it still running good compression, like 150+ ?

Dont know the PSI, but leakdown was less than 1%

http://www.youtube.com/user/500bigbore · Post by **Roostius_Maximus** » December 3rd, 2010, 7:20 am

The work below the jug makes much more difference even on the ported jug than the topend work does over stock.
Beyond porting the customers parts, I'll have miltiple sets of cases and cylinders ready to be sold outright by early january.

dubious01 · Post by **dubious01** » December 25th, 2010, 11:32 pm

Roostius_Maximus wrote:The work below the jug makes much more difference even on the ported jug than the topend work does over stock.
Beyond porting the customers parts, I'll have miltiple sets of cases and cylinders ready to be sold outright by early january.

CANT WAIT TO RUN IT!

2strokeforever · Post by **2strokeforever** » April 2nd, 2012, 11:51 pm

one day i will have to throw the stock ignition on, borrow 4strokejokes bike, tune it (jet, silencer packing, check reeds), and take both bikes to a dyno and get some charts

too bad when we were out my bike had the loose coil bolt causing misfiring

seanmx57 · Post by **seanmx57** » April 27th, 2012, 7:27 am

AlisoBob wrote:
hoofarted wrote: I am curious about this too. IIRC, you mentioned the bottom being soft - is that b/c of the lean condition?
Yea... thing pulls like a sum-bitch now.

Since I added a new top end, porting, and a V-Force reed block all at the same time, its hard to tell what did what...

Power is stronger bottom to top.... maybe 10% more down low, 20% more up top...

I need longer sleeves for my jersey now....

So what settings did you end up changing in the carb to dial it in? Still using a DGN?

Post by **AlisoBob** » April 27th, 2012, 7:47 am

More gas....more gas.

BannedCR500Riders.com

TWIRP Jetting Thread

TWIRP Jetting Thread