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Old 10-26-2013, 01:56 AM   #2926
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Originally Posted by CristianTabush View Post
Please, take my comments with a grain of salt. I don't think my word is the final authority by any means, but my findings were almost too good to be true. Speculation is exactly why I qualify my statements.

This past week I tested the BD7 in less than "perfect" carpet conditions. Grip was at about 85% and my lap times were consistently 2 tenths faster than with my RX4. The RX4 was by far the best set-up car I had driven on our track until this week. I have been fine tuning the set up for several months and on the particular layout all of last week I worked on a vast array of conditions to get the car really good. My fast lap was a 9.55 or so. I could hit 9.7's pretty regularly. This was on fresh rubber and with tons of track time. Track conditions were pretty good as well. I also must add, I only run mod.

The Yokomo I received Monday night and I hit the track on Tuesday evening. Ran 2 packs through it with mostly standard parts. I hit consecutive 9.6's for the first time with the layout and I had never had a perfect lap. On Wednesday, I focused on adjusting 1 thing at a time to learn about the car. I also installed some optional parts and carbon arms. Some adjustments made me go in the wrong direction, some made me get better. As I slowly started heading in the right direction I started noticing how much quicker the car got around the twisties. The car carried more corner speed and was easier to drive fast around the track. By the end of the night I was starting to hit tons of 9.6's, but the car was still not perfect. On Thursday I just made a few geometry changes and started going backwards. So I reverted a bit back and went to thicker diff oil. The car went from being a 9.6 car to a consistent 9.5 and a few 9.4's A bad lap was now a 9.6. All this was also on old tires, which made it more impressive as the Sorex 28's we run are much faster on the first 2 runs. The BD7 is easier on tires I think. With Sorex 28's, you get a lot of overheating and squealing on carpet, the more you squeal, the harder the car is to drive. The XRAY tends to squeal slightly more, which is why it probably needs new tires, with a hard sidewall to go faster.

The car for me generates better forward thrust than the T4. It gets from point a to point b better. This might not be as noticeable in stock, but in mod, it's huge. The car is also faster in smaller radius sweeping corners, where it digs into the track better. The XRAY requires a bit more finesse in this type of corner.

It is important to say that the BD7 probably requires sharper reflexes than the XRAY. It is more responsive, which probably is a better fit for me.

Both cars are fantastic, and in the right hands, both can be winners. However, racing mod, the BD7 is far more at home and it is more effective in achieving consistent fast laps at our track, with the tires we use. We do keep developing our T4 everyday. Now we have a higher benchmark in house with the yokomo to chase after.

Sounds good.


What would you have done differently with the Xray parts had you driven this car when it first came out over a year ago?
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Old 10-26-2013, 08:29 AM   #2927
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New bulkheads to key everything in. This is big. Our layshaft bulkheads are keyed in. They should arrive soon. (They have been delayed by 2 months because they can't get Orange done.)

Aside from that, I am not sure I would change much with what we have done. The T4 is a well though out design and works awesome. Our changes are subtle and in part inspired by cars such as the Yokomo. The rest of the stuff we make are accessories that give you more tuning options.
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Old 10-26-2013, 09:41 AM   #2928
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While I have test driven several other modern tourers, the BD7 is the only one I own, and see no greener pastures as yet

Was just playing the devils advocate, as at our track there are a few "car of the week drivers", and they always seem to go the same pace no matter what brand they run

The BD7, easy on tires, and works well on used tires
Yes, yes it does, thanks for your insight Christian

Care to post a setup ?

Oh, and Happy Birthday
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Old 10-26-2013, 10:55 AM   #2929
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Corey, I have further questions for you. As you suggested, I wanted to try your IIC setup which was very close to Ronald's as you said. All went well except one thing. 3mms of rear droop means over 7mms of downstop!!! This is never stated anywhere anytime, in a setup sheet. Taking new carpet starting setup from "Team yokomo" facebook page as an example, they say use rear downstop about 4.5-5.5mms. Other than that, rest of the setup is basically same except the rear link. Please enlighten me about downstop/droop setups that you, Ronald and other top guys use.
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Old 10-26-2013, 07:01 PM   #2930
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How cool is this ?

+ YouTube Video
ERROR: If you can see this, then YouTube is down or you don't have Flash installed.
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Old 10-27-2013, 02:17 AM   #2931
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Originally Posted by fasfury View Post
Corey, I have further questions for you. As you suggested, I wanted to try your IIC setup which was very close to Ronald's as you said. All went well except one thing. 3mms of rear droop means over 7mms of downstop!!! This is never stated anywhere anytime, in a setup sheet. Taking new carpet starting setup from "Team yokomo" facebook page as an example, they say use rear downstop about 4.5-5.5mms. Other than that, rest of the setup is basically same except the rear link. Please enlighten me about downstop/droop setups that you, Ronald and other top guys use.
I think you're confusing the terms a little, which happens often with droop for some reason.
If you use roughly 5-5.5mm ride height, 63mm ish tyres, and set your droop under the wishbone at about 4-5mm you will have somewhere in the region of 3mm up travel.
Also the centre of your outer hinge pin will be around 7mm off your setup board.

3mm rear up travel and 2mm front will be a pretty close starting point for anywhere, as Corey has mentioned in this thread once you're close it's all about fine adjustment.
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Old 10-27-2013, 07:05 AM   #2932
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3mms of rear uptravel(droop) means that about 7mms of downstop is needed under the upright! This means if we try to run 6 front and 5 rear downstop, we would have a lot more uptravel (about 5mm) than we should, and this results in a very twitchy car to drive. It changes the car behaviour completely. However, if we just go from measuring the uptravel and set it to about 3mms, we think that car handling will improve big time, but we are puzzled that after setting 3mm uptravel, it is measured 7mms of downstop value under the upright, not from pin centre!!

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Old 10-27-2013, 01:17 PM   #2933
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Alright I've been been squeezing every last drop of performance out of my serpent s400 for the last 6 years. I think it's time to upgrade.

I was seriously considering the t4 14 until I saw this thread.

I'm a socal 17.5 nt racer who will be racing primarily at tq raceway (medium-high grip carpet) and our new local asphalt track (medium to low grip).

I've poured over the thread looking for someone to say something bad about this car but it doesn't look like I'll find it.

Question:
Is this car over kill for a b-main 17.5 racer. It seems like everyone who loves this car is racing at least 13.5. I know Im not as fast as those guys and if I could get away this a used t4 or tc6.1 and not notice a difference I would prefer to save some coin.
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Old 10-27-2013, 01:21 PM   #2934
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BD7 did really well in the UK clubmans 17.5 championship.
It would be fair to say the UK has low-medium grip tarmac tracks.
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Old 10-27-2013, 01:28 PM   #2935
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hi guys probably a really derpy question
in the back of the manual we have our lovely 64 n 48 pitch gear charts.

But why is half of the chart in white and then a selection in grey, my mind is telling me that those in grey under a spur gear a pinion in grey wont fit but white will..am i right in thinking that? because a 40 tooth pinion i cannot physically get close to a 96t spur on 64 pitch and that for example is in grey not white.
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Old 10-27-2013, 01:28 PM   #2936
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Quote:
Originally Posted by cyclonetog View Post
BD7 did really well in the UK clubmans 17.5 championship.
It would be fair to say the UK has low-medium grip tarmac tracks.


That Set up used in tracks used in uk?
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Old 10-27-2013, 02:06 PM   #2937
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I don't know what the 17.5 guys were running because I didn't go to the Clubmans rounds but I can't imagine they were too far from the Yokomo base setups, nothing ever seems to be too far from them.
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Old 10-27-2013, 02:11 PM   #2938
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Quote:
Originally Posted by PurcyP View Post
hi guys probably a really derpy question
in the back of the manual we have our lovely 64 n 48 pitch gear charts.

But why is half of the chart in white and then a selection in grey, my mind is telling me that those in grey under a spur gear a pinion in grey wont fit but white will..am i right in thinking that? because a 40 tooth pinion i cannot physically get close to a 96t spur on 64 pitch and that for example is in grey not white.
Yes the grey ratios don't physically fit, there's either a gap or an overlap at max adjustment.
You can still use the chart to work out how to do what you're trying to get to, so 96/40=4.8:1
Looking at the white section 108/45 would get you to the same ratio.
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Old 10-27-2013, 03:22 PM   #2939
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Yeah as i thought, thanks cyclone! i wanted a FDR of around 6.4 anyway as i forgot im running 13.5t boosted, makes sense as to why they call the 116t modified and 96t stock.
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Old 10-27-2013, 05:02 PM   #2940
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Quote:
Originally Posted by PurcyP View Post
Yeah as i thought, thanks cyclone! i wanted a FDR of around 6.4 anyway as i forgot im running 13.5t boosted, makes sense as to why they call the 116t modified and 96t stock.
You can also run smaller Spur gears for a taller ratio than what the chart shows, this could be useful for 17.5 blinky
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