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Old 01-04-2010, 09:29 PM   #81 (permalink)
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Originally Posted by hkeller View Post

Question for Pro Mod, if I ever get a 6.5, just for giggles, will this jackshaft also work on it? Man, that would be one heck of a fun little bike for adult riders.
i asked him about that when these first came out, he said they should but never tried it.
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Old 01-04-2010, 11:04 PM   #82 (permalink)
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Thanks hkeller!
Glad your happy with your purchase!
I did not notice you were a OMB.com member when the order went through. It does not matter if your new. This is one awesome Forum and I'm glad you joined up too.
I just sent you a paypal refund so you get the OMB discount price.
As far as your question about the J.S being used with a 6.5 ....
There are pics of the PMR J.S system being used with the 6.5 engine on my website at
Baja Doodlebug,Dirtbug Performance and Repair parts It works great for many applications that can benefit from a gear reduction system. When using one for a 6.5 DB project you need to use the PMR mount plate that is available on the website too so you can set up your chain alignment. (engine mounting will be about 3/8" more to the right than if you just run a chain from the clutch to the rear sprocket).
If you are going to just run a stock 6.5 engine with the Governor intact then the JS system will not really be that practical. The stock 6.5 makes enough torque to pull the 12-70 5.83 ratio OK. If you are going to run a modified 6.5 without a Governor then you can gear down with the JS system to get better take-off accell, smoother clutch action, and still have a blazing top speed because of your modified engines increased RPM capability. It's my opinion that the jackshaft makes a Hotrod 6.5 DB more fun to ride rather than trying to go for maximum top end speed with tall gearing. I like a 7 to 7.5 to 1 ratio on the bike I play with. But if anyone wanted to get crazy and try to set a land-speed record they could always change up the JS gearing to overdrive. Anyone have a Doodlebugger land speed record yet? lol
Hope this helps explain.
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Old 01-05-2010, 09:34 AM   #83 (permalink)
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I received your refund. Thank you. That was not necessary, but it speaks extremely well of you. It is one in a million merchants that would provide an unrequested discount.

Your product is well worth the original price I paid and then some. The smile on my son's face was worth every penny.

Best regards to you.

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Old 01-06-2010, 01:23 PM   #84 (permalink)
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This is amazing! I am new to the mini bike world and already learning so much! I have a 14 year old and we want to do something together , father and son . We have the DB30 and I am looking to make the bike nice for him . Thanks
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Old 01-25-2010, 02:21 PM   #85 (permalink)
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Another satisfied customer. Great service/fast shipping. Product as described. Installed with no problems. DB runs great! Thanx Brad!
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Old 01-25-2010, 07:03 PM   #86 (permalink)
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My 6yo daughter rides our DB30 just fine but when my 14yo son gets on it's flintstone time, as for my 225# ass forget about it! This looks like a great alternative to repowering! I have a BMI/comet jackshaft n.i.b. but am saving it for another project. Look for me to buy this product in the near future as my daughter's confidence grows!
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Old 02-06-2010, 02:05 AM   #87 (permalink)
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Please PM me with current pricing info for members. Thanks!
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Old 02-23-2010, 07:36 PM   #88 (permalink)
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I just bought a jackshaft.I tested it out today in the street,and it dident seem to reach the same speed as before.Is their anything i should change to get it going a little faster?And Can I get that discount for the jackshaft? I just ordered it last week.
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Old 02-23-2010, 08:36 PM   #89 (permalink)
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Write Brad to see what can be done at
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Old 02-23-2010, 09:51 PM   #90 (permalink)
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A properly tuned 2.8 engine should reach around 27mph with a jackshaft system setup with the 13t-18t sprocket combo. I have heard of some Stock geared DB's being able to maybe hit 30 on flat ground and with a light rider. But without the JS system the acceleration and hill climbing performance is very poor. You can play with the gearing and install a 14t in place of the 13t and get more top speed. But as you gain top speed you will loose take off speed and hill climbing performance. You can easily tune the bike to your needs.
Also make sure your throttle stop screw down on the linkage where the cable hooks up is backed out all the way or even remove it. The governor will still keep the engine from over speeding.
PM me or call me and I can help with different sprocket choice's. We can also talk about the discount. Any members still interested in a OMB discount can PM me before they place the order and I will set you up with the reduced price.
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