Chain Linkin's - DB Dirt Racer - (Chinese Class)

#1


Bought this bike late last spring and added just enough bolt-on parts to have it ready for our race season (Note the paint can lid number plates with the always classy zip-tie mounts). Now that our season is finally over it's almost time for a complete tear down and proper rebuild. I say almost because we still have one more race event: our Winter Classic, a bragging rights only race, held during the worse time of year. That race is planned for some time in February, that's why the bike is still fully assembled.

This post is a bit preemptive but I wanted to make sure I was in before Feb. 1st. I do have a few parts I have started working on but the bike won't be touched until after our race.

Plans:

New fuel tank - from some old propane tanks
Modified/lowered fenders
A few modifications to the frame
Proper number plates
I'm going to modify the seat somehow...still debating

I'm hoping to do some mild engine molds and compete engine rebuild.

and I'm sure there will be other items along the way.

I also wanted to say thanks to every one putting this on this year. Although I haven't been very active on this site since originally joining I have always enjoyed following along with the builds.
 
#3
Like I mentioned above, I have started on some components that will be added during the rebuild.

Here is my rear new fender. The first order of business was to extend my rear fender. My end goal is to build some mud flaps to replicate the style of old rally cars. Here is what I have done so far:



The two parts were butt welded with braces on the under side (Thank you SidePocket) After cleaning up the joints I removed the middle section of the fender and added a strip from my old furnace cover.





Originally I had planned to weld this but I decided on rivets - true dirt track style. I do plan on giving this bike a new coat of paint but right now I am really enjoying the "furnace green" and primer red...:laugh:

Test fit up - you can see in the top of the picture where the original fender sits. Can't lie, this modification was inspired by FatBoy04's build off bike from last year. (if he sees this - let me know if that project was ever finished :thumbsup:)

 
#7
Like I mentioned above, I have started on some components that will be added during the rebuild.

Here is my rear new fender. The first order of business was to extend my rear fender. My end goal is to build some mud flaps to replicate the style of old rally cars. Here is what I have done so far:



The two parts were butt welded with braces on the under side (Thank you SidePocket) After cleaning up the joints I removed the middle section of the fender and added a strip from my old furnace cover.





Originally I had planned to weld this but I decided on rivets - true dirt track style. I do plan on giving this bike a new coat of paint but right now I am really enjoying the "furnace green" and primer red...:laugh:

Test fit up - you can see in the top of the picture where the original fender sits. Can't lie, this modification was inspired by FatBoy04's build off bike from last year. (if he sees this - let me know if that project was ever finished :thumbsup:)


Love it, Nice Job!!Still work in progress, mostly fighting a real shake when taking off.
 
#11
Can't. let. my. thread. hit bottom..... :freakout:

I was wondering if anyone here has dealt with Robertson's torque tubes? I sent them an email last week regarding one of their headers and haven't heard anything back. I have been putting off the phone call since it's long distance/international.

As far as my mini goes, not much has been done since my last post. Spent this past weekend working on my garage. This project is going to be a weekend to weekend thing for the next couple of weeks. Hopefully will have my new fuel tank started soon.
 
#12
Looking good man. I agree %100, the fenders need to be lowered on the DB 30' and dirt bugs, especially the front one.

Really looking forward to coming out in the spring time to see what all this race action is all about! In the mean time I'm going to build up myself a Dirt Bug with a 6.5 Honda GX200 and a quality Cent clutch so I can race with you guys.
 
#14
Like I mentioned above, I have started on some components that will be added during the rebuild.

Here is my rear new fender. The first order of business was to extend my rear fender. My end goal is to build some mud flaps to replicate the style of old rally cars. Here is what I have done so far:



The two parts were butt welded with braces on the under side (Thank you SidePocket) After cleaning up the joints I removed the middle section of the fender and added a strip from my old furnace cover.





Originally I had planned to weld this but I decided on rivets - true dirt track style. I do plan on giving this bike a new coat of paint but right now I am really enjoying the "furnace green" and primer red...:laugh:

Test fit up - you can see in the top of the picture where the original fender sits. Can't lie, this modification was inspired by FatBoy04's build off bike from last year. (if he sees this - let me know if that project was ever finished :thumbsup:)

I'm loving that rear fender :thumbsup: I'll be watching this build !
 
#15
Yeah, it's going to be great. I should have called this the LOMBRA Dirt Racer Build, I simple how to guide explaining our bike rules.
Hey that'd be great. I don't want to show up with a built up bike and be "out of spec" so to speak lol.

I noticed in your pics you have a rather large idler pulley for the drive chain. Is this an idler pulley off a rider mower deck or something?

I plan on using the OldMiniBikes header/muffler pipe for mini bikes, velocity stack with pod air filter, richer jetting and maxed out governor settings. Would this be okay to run?
 
#16
Yeah, that pulley is a princess auto special :rolleyes: The engine location is none adjustable and this caused the scenario where I couldn't get the chain length right. The limited chain tensioner travel on the bikes wasn't enough, thus, over sized pulley. I'm getting the OldMiniBikes split sprocket set up so all that non-sense with be dealh with during this build. There are also plans to fabricate a new tensioner set-up.

As long as the engine block was a stock 6.5 at one time and remains pull start you'll be ok. Our track doesn't really allow you to get wide open on the throttle so leaving the gov' on won't hinder you any.
 
#18
Test fit up - you can see in the top of the picture where the original fender sits. Can't lie, this modification was inspired by FatBoy04's build off bike from last year. (if he sees this - let me know if that project was ever finished ) Glad I inspired you and you pushed me to finish the bike. No cat grill yet, but working on it .
DSCN0401.JPG DSCN0400.JPG
 
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#20
Yeah, that pulley is a princess auto special :rolleyes: The engine location is none adjustable and this caused the scenario where I couldn't get the chain length right. The limited chain tensioner travel on the bikes wasn't enough, thus, over sized pulley. I'm getting the OldMiniBikes split sprocket set up so all that non-sense with be dealh with during this build. There are also plans to fabricate a new tensioner set-up.

As long as the engine block was a stock 6.5 at one time and remains pull start you'll be ok. Our track doesn't really allow you to get wide open on the throttle so leaving the gov' on won't hinder you any.
Ahh I see. So you don't use one of those billet aluminum mount plates then?

Yeah that's sweet that you can get aftermarket DB 30 rear sprockets but the stock ratio one should be fine right?

Okay sounds good. I don't plan on anything major, just light mods. I do want a higher stall clutch then 2200 rpm tho!
 
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