My 2nd Baja build will be OBR Twin Powered

IETZR1S

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Woodland Hills, CA
That thing is sick Brian. I wish they had another crank laying around. Sean told me he would pull out some old port maps if I could drum up a crank but no luck. I'm staying a 57 I guess:(
Thanks Dan, MB is running strong. Got well over 10 hours on the bottom end with no issues or problems to report. I know the crank Team OBR got for me was a prototype. There is no reason for OBR not to be putting them into production. It would not surprise me if you saw some more OBR 61cc twins working their way around the forum. There are 3 that I know of.

I am currently running 28/46 and just installed the 33/41, they both sound wicked. Still looks and sound good Brian.
Thanks Joe, I am going to be keeping the small gears on for a little bit. I will get some more video of MB laying rubber.

Really cool baja a sounds like a hopped up banshee!!!
Thanks Ratpower!!! Monster Baby runs like a pissed off Banshee too. ( No Pun Intended Dan)
 

banshee

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Minnesota
Lol...sweet, thanks buddy. I've dropped your name multiple times when asking Sean for favors and it always ends up costing me MORE money! Gonna start using a different name :)
 

IETZR1S

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Lol...sweet, thanks buddy. I've dropped your name multiple times when asking Sean for favors and it always ends up costing me MORE money! Gonna start using a different name :)

:lol::lol::lol:.... I pay more and expect more myself. If you drop my name just know it will cost. My set up is not low dollar.
 

zignzag

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North Vancouver, B.C.
Looks awesome. Just wondering why do people use small wheels and tires for speed runs. Is it so the car doesn't wheelie if u use a twin. Would be really easy to burn up those tires with a twin and hard to get grip with small wheel/tire combo I would think. Is it easier to control speed runs with that set up.
 

IETZR1S

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Looks awesome. Just wondering why do people use small wheels and tires for speed runs. Is it so the car doesn't wheelie if u use a twin. Would be really easy to burn up those tires with a twin and hard to get grip with small wheel/tire combo I would think. Is it easier to control speed runs with that set up.
Thanks Zignzag. I used to run BRP 5.9-6.2 slicks. The tires have tons of grip.. I ran them over 100mph. I never had one let go during a speed run. I was pleased with them for the time. I wanted to go faster. Monster Baby had to loose weight. Switching to the 4.6" GRP tires saved MB 2lbs. of rolling weight. That is a noticeable gain. The 4.6" tires also lowers the center of gravity and the roll center of the chassis. I have OD gear ratios from Lee Watson @ BlackBone to compensate for the smaller tires. The smaller tires help MB spool up quicker. 1.1 and over drive ratios keep her flying on the big end. The over all set up of smaller tires is easier for me to drive. The 4.6" GRP tires I run are belted. They do not grow at the speeds I am currently running. I warm my tires up before speed runs. The small tires are like competition tires for 1.1 cars. They work best once warmed up.
 

dscjester

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NJ
Lol...sweet, thanks buddy. I've dropped your name multiple times when asking Sean for favors and it always ends up costing me MORE money! Gonna start using a different name :)
I drop his name and they charge me more.....:hammer:
 

IETZR1S

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I took MB back out today for a quick spin. I wanted to torture and pusnish the rear tires today. I still had 28-46 gearing bolted on. Monster Baby left rubber and smoke all over the OBR parking lot. I would like to wish all HBF and their families and safe and happy new year. May we all have a better 14 than 13.
Here is a small video from today.

[ame]http://youtu.be/JqIp4PPkOgU[/ame]
 

IETZR1S

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Woodland Hills, CA
I walked into my shop to get my rc gear. I found the water heater had been puking for hours. I did not get to go for speed runs today. Leaking water heater changed my day. Took Monster Baby out for a local spin. She ran so good. I felt bad I had MB caged up on a tiny street. She wants to stretch her legs. Still have the 28-46 Blackbone gearing bolted up. Ran 1 tank of fuel with no issues or problems other than lack grip. Still on the PMT touring car tires out back. They really suck for traction. Saving my good rubber for speed runs. Today I got 10.4 miles/16.7kilometers on a tank of fuel. Looking forward to getting back to speed runs shortly.
 

IETZR1S

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Woodland Hills, CA
I had some time to work on Monster Baby today. I have been running the AMS HPI/FG 4pc. kit at all four corners. I did not like the fact of running triple digit speeds with e-clips holding my front wheels on. I am getting her in shape for speed runs. I had some of Daniels Pitstop HPI/FG wheel adapters. They would increase the front track width. I tried getting them on today. 1 was not problem. The other was not made right. I broke it trying to modify it to work. I am sure Daniels Pitstop would have warrantied it. I just did not feel like going through the hassle and time of shipping back and fourth. So...still determined. I had some AMS HPI/FG rear adapters and some Vertigo clipless front axles laying around in the parts stash. I installed everything with out any issues. My front wheels are now wider than the rear. This should help make MB more stable and easier to drive at triple digit speeds. I have increase my front track width from 18.5"/470mm to 19.75"/501mm. Here are some pics of the install and change over.









 

IETZR1S

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Woodland Hills, CA
It was time to get back into speed runs with Monster Baby. I put MB on the scale before I left. She is 28.6lbs/13.0kg dry no fuel. Today I bolted up 33P-41S and ran with GRP 121mm rear tires. Its been awhile since MB and I made some runs down the strip. Figured med. size gear would work to shake the bugs off the two of us. I went out solo and walked the fresh tarmac. I did not run MB in as deep as I usually do. Without support I am too far from the braking zone if a 1.1 came into play. So I played it safe. Monster Baby laid down 86.2mph/138.7kph @ 18,360rpm on the 1st pass. Ran a little deep in and backed it with 86.7mph/139.5kph. I am sure if I ran it another 300ft./90+met I could have gone faster. Ran into a slight snag today. After pass #2 it stalled out. Went to re fire and broke a pull start rope. Installed a new pull start rope went to move MB, sounded like a slipping clutch and she wouldn't even roll. Went to change the clutch track side. Got it apart and it was all perfect:detective:. Spun the rear wheels and heard grinding. My trans was not fine. Got it all apart, found a bad bearing on the idler gear. It got hot and folded in the case. I will be placing a ddm order tomorrow.
Here are some pics from today.







 
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